What is the hardest mental illness to live with?

In this guide, we will discuss “What is the hardest mental illness to live with”, why people develop mental illnesses,  what is Borderline Personality Disorder (BPD), why BPD tends to go undiagnosed, treatment options and a few other difficult or hard mental illnesses to live with that are not very common.

What is the hardest mental illness to live with?

The hardest mental illness to live with is considered to be Borderline Personality Disorder, because of all the comorbid conditions associated with it as well as the emotional instability it brings about. Although all mental illnesses are hard to live with, BPD can encompass problems from various issues, making it one of the hardest mental illnesses to live with.

When you think about what the hardest mental illness to live with is you may say the first thing that comes to mind like depression, anxiety, schizophrenia, autism, and probably you wouldn’t be wrong at all. Every mental illness has a different set of symptoms that makes it the hardest mental illness to live with according to the sufferer. 

However, from an objective point of view, some experts have indicated that Borderline Personality Disorder seems to be, not only the hardest mental disorders to live with but also the most difficult to treat. However, with newer scientific evidence, treatment is said to reduce the severity of the symptoms, improve functioning and quality of life. 

Why do people develop mental illnesses?

There are many factors associated with the risk of developing a mental illness. For instance, if we specifically talk about personality disorders, we can’t determine the precise cause but factors that increase the risk of developing a personality disorder include:

  • Family history of personality disorders or other mental health illnesses.
  • Being in an abusive, unstable, chaotic environment during childhood.
  • Being diagnosed with childhood conduct disorder.
  • Changes in your brain chemistry and/or structure.

Moreover, many scientists and researchers have indicated that genes may have

something to do with developing a personality disorder such as BPD. For instance,

certain personality traits that are passed from your parents to you genetically are

said to put you at a higher risk of developing personality disorders.

However, we can’t just blame it on genetics alone. As we have mentioned, your environment can contribute also to increasing the risk. For example, your experiences, the surroundings you grew up in, traumatic events that occurred and even relationships with family members and others can make you vulnerable to developing a personality disorder. Consequently, we are talking about genes plus the environment and certain triggers

What is Borderline Personality Disorder?

Borderline Personality Disorder often referred to as BPD. According to the National Institute of Mental Health:

“Borderline personality disorder is an illness marked by an ongoing pattern of varying moods, self-image, and behaviour. These symptoms often result in impulsive actions and problems in relationships with other people. A person with a borderline personality disorder may experience episodes of anger, depression, and anxiety that may last from a few hours to days. Recognizable symptoms typically show up during adolescence (teenage years) or early adulthood, but early symptoms of the illness can occur during childhood.”

Moreover, even if living with BPD can be considered difficult due to having unstable

relationships, emotional reactivity and dysregulation, among other characteristics,

many people with BPD don’t even know they have it. This is why BPD is one of the most misdiagnosed conditions there are. 

Why does BPD go undiagnosed?

One of the reasons it goes undiagnosed is because it tends to share some of the symptoms with other mental illnesses such as depression, anxiety, post-traumatic stress disorder,

bipolar disorder, eating disorders, among others. Evidence has indicated that BPD

is commonly misdiagnosed as Bipolar Disorder Type 2, most likely due to some

similar symptoms. However, getting the correct diagnosis is crucial to find the

appropriate treatment.

Are there treatment options?

Here are some of the most effective treatments for BPD:

  • Dialectical Behavior Therapy (DBT)
  • Transference-Focused Therapy (TFP)
  • Mentalization-based therapy (MBT)
  • Cognitive Behavioral Therapy (CBT)
  • Schema-focused therapy
  • Systems training for emotional predictability and problem-solving (STEPPS)

As indicated by the National Institute of Mental Health, specifically referring to DBT and in regards to the treatment, it “was developed for individuals with a borderline personality disorder, uses concepts of mindfulness and acceptance or being aware of and attentive to the current

situation and emotional state. DBT also teaches skills to control intense emotions, reduce self-destructive behaviours, and improve relationships.”

Other mental illnesses

There are many illnesses, disorders or syndromes that can be very difficult to live with. Here we will mention some of the most uncommon and hardest to live with according to their description. 

Alice in Wonderland Syndrome (Todd Syndrome)

This may sound like it was dragged out of a fantasy movie but it is a real syndrome. This syndrome causes one’s surroundings to appear distorted just like Alice appears as growing too tall in the story, people who suffer from this syndrome will hear sounds either quieter or louder, objects appear smaller or larger than they do in real life and they will even lose the sense of accurate velocity or textures.

However, this syndrome is considered extremely rare and in most cases, it starts affecting people in their 20s who have had a history of a brain tumour or drug use.

Alien Hand Syndrome

This has to be one of the rarest and scariest syndromes. People with this syndrome experience a complete loss of control of a hand or limb. They are convinced that the hand or limb has a mind of its own and sufferers have been reported that this ‘alien’ hand or limb has got to the point of wanting to choke them or rip their clothes off. 

It is believed that this syndrome is more common in patients with Alzheimer’s disease or Creutzfeldt-Jakob Disease. However, it can also result from a brain surgery in which the communication between two hemispheres doesn’t exist anymore. There is no cure for this syndrome and people affected by it opt for keeping their hands occupied.


Apotemnophilia is also known as Body Integrity Disorder or amputee identity disorder. This is considered a neurological disorder which is characterized by the overwhelming desire to amputate or damage parts of the body which are healthy. There is not much about this disorder out there but it is believed to result from a lesion to the right parietal lobe in the brain.

Since doctors will not just simply amputate a limb because their patient is asking them to then they will attempt to do it themselves so it can become a dangerous condition.

Capgras Delusion

This condition gets its name from French psychiatrist Joseph Capgras who was fascinated by the illusion of doubles. This is a very debilitating disorder in which the sufferer believes the people around them have been replaced by imposters and those imposters are believed to plot to harm the sufferer.

This condition is relatively rare and it is often seen when there is a brain injury or trauma, or those who have been diagnosed with dementia, schizophrenia or epilepsy.

Cotard Delusion

This is a scary mental illness in which the sufferer believes that they are a zombie (walking dead) or a ghost, and their body is decaying and/or they believe they have lost all their blood and internal organs. Having the feeling of a rotting body is normally part of this delusion. Also, many people with Cotard seem to experience severe depression. This is a very rare condition first described in 1880 by neurologist Jules Cotard.

Hoarding or Diogenes Syndrome

If you think about the TV show ‘Hoarders’ you are right. This syndrome is considered to be one of the most misunderstood mental illnesses and it is named after a Greek philosopher called Diogenes of Sinope. This syndrome is characterized by the overwhelming need/desire to collect seemingly random items, where the sufferer develops an emotional attachment.

In addition to hoarding, people with this syndrome often display extreme self-neglect, apathy towards others or themselves and social withdrawal. It seems to be more common in people with dementia or those who have suffered emotional trauma, abandonment or lack of stability in their lives.

Why is this blog about What is the hardest mental illness to live with important?

There are many mental illnesses and some of them are considered very rare but not because they are uncommon it means they are easy to live with. As we have mentioned, BPD is considered by many experts to be one of the most difficult to treat as well as to live it. Moreover, it goes undiagnosed because the symptoms overlap with other conditions and most of the time the sufferer won’t seek treatment.

In contrast, we have mentioned other rare but scary mental illnesses to live with even if most of them are considered uncommon due to their characteristics and the specificity of the reasons it tends to present (i.e. brain tumour, injury to a specific lobe, etc.). However, subjectively speaking, anyone living with a mental disorder will say how debilitating and hard it is to live with such a condition, which is still valid no matter what experts may say.

Please feel free to leave any comments or thoughts about the content of this article!

Frequently Asked Questions (FAQs) about What is the hardest mental illness to live with

What is the most difficult mental illness?

Everyone experiences and struggles with mental illnesses in a different way. However, some argue that personality disorders are not only the most difficult to treat but also to live with. In many cases, people don’t seek help because they can function in their day to day lives.

What are the 7 types of mental disorders?

The 7 types or categories in which mental disorders can be divided are:

– mood disorders (such as depression or bipolar disorder)
anxiety disorders.

– personality disorders.

– psychotic disorders (such as schizophrenia)

– eating disorders.

– trauma-related disorders (such as post-traumatic stress disorder)
substance abuse disorders.

What is the rarest mental illness?

Some of the rarest mental illnesses are:

– Stendhal Syndrome

– Apotemnophilia

– Alien Hand Syndrome

– Capgras Syndrome

– Alice in Wonderland Syndrome

What is considered a serious mental illness?

According to the NIMH, “A serious mental illness or SMI is defined as a mental, behavioural or emotional disorder that results in serious functional impairment, which substantially interferes with or limits one or more major life activities.”

What are the top 10 mental illnesses?

Here is a top 10 most common mental illnesses:

– Depression. 

– Generalised anxiety disorder.

– Panic disorder.

– Obsessive-compulsive disorder. 

– Post-traumatic stress disorder. 

– Social anxiety disorder. 

– Specific phobias.


Nimh.nih.gov: “Borderline Personality Disorder”

Onlinepsychologydegree.info: “15 Scariest Mental Disorders of All Time”

Fruzzetti, A. (2017, Oct.) Why Borderline Personality Disorder is Misdiagnosed. Retrieved from Nami.org.

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