I can only speak from my own experiences within the mental healthcare system. I will do my best to keep my tinfoil hat off, but everything below is based on personal, lived experience. I'm not a doctor, a healthcare professional or a scientist, and you can decide for yourself whether that's for better or for worse.
In my opinion, a lot of what is called mental illness is a societal construct rather than an actual illness. Say that someone has glaucoma. There is a very definite physical change within the body that can be measured and observed. In all fields of medicine, nothing is certain. Human knowledge is (generally) constantly expanding and changing, so one given case of what may be diagnosed as glaucoma today could actually be considered another condition entirely in, say, 50 years' time. Misdiagnoses also occur. You may go to one ophthalmologist and be told you have glaucoma, but decide for a second opinion and are instead told you have something else. Whom do you believe? What is right? Either way, there is a definite physical occurrence within your eyes that can be seen (with the right equipment), measured and, hopefully, managed.
Mental illness, and psychiatry, in my own experience, doesn't work that way. I believe the brain is the least understood part of the body. There is so, so much modern science just doesn't know yet. But, just as someone may walk into their optometrist to complain of poorer peripheral vision of late, someone may go to a psychiatrist to report excessive sadness, overwhelming anxiety, disturbing hallucinations, or any number of concerns. The trouble is, blood tests won't show an increase in sorrow. Faecal samples don't have signposts in them that read 'Anxiety'. An MRI won't turn up with images of the hallucinations. Science does, admittedly, understand some aspects of the brain. Things like SSRIs were developed with aim for a very particular mechanism. But for a lot of 'modern' medications and treatments, the actual process by which they work is generally not actually known with any degree of certainty. They just seem to work better than placebo or nothing in controlled studies, so they slap them on the market.
Consider 'depression' alone. Diagnosing someone with 'depression' and saying you will treat them for 'depression' is, as far as I'm concerned, akin to saying they have 'bad eyesight' and that you will treat the 'bad eyesight'. But the psychiatrists and psychologists I have had the misfortune of being under just slap the label on you, then do what supposedly works for X% of patients, and tell you to come back for review in 4-6 weeks. They don't aim to find why you are exhibiting the symptoms you experience. They just pick a label that suits what you're describing and exhibiting, scribble down a prescription, lock you up if you're unlucky, and go home, knowing with great confidence that they've contributed to someone's health.
If someone you love dearly dies, and you are overcome with sadness for months, years, are you depressed? If you have a physical disability that causes chronic pain, making existence suffering, are you depressed? If some invisible switch in your brain was flicked the wrong way before you were ever born, and you can see only sorrow and misery wherever you look, especially within yourself, are you depressed? If all of these are depression, how can all of them be treated the same way?
Mental healthcare unfortunately is a branch of actual, physical healthcare. Symptoms are considered, scientific tests are performed, a diagnosis is made, treatment is administered. I maintain that none of the tests in psychiatry are scientific. Asking me to rate my mood on a scale from 1 to 5 is not scientific. You don't see someone brought into the emergency department with a broken leg, and rather than order an X-ray, the doctor asks how painful it is, then makes the diagnosis based on that. But as science currently stands, there are no reliable scientific methods for determining mental illness. Again, the brain is mostly a mystery. The scientific community knows a lot more about it than, say, 100, 50, 25, even 10 years ago. But it's a flickering candle of knowledge in an infinite abyss of the unknown.
How can you diagnose a condition based solely on reported or observed symptoms? It does happen occasionally in the physical healthcare world, yes. But it is not general practice. It leads only to confusion, most of all for the patient. I've had many psychiatrists, though most were ones forced upon me through involuntary admissions. I've had 7 that I saw as an outpatient, each for a period of a minimum of 6 months, though generally it was at least 1.5 to 2 years for each. Apparently, I have treatment-resistant depression, anxiety, autism, ADHD, bipolar disorder and PTSD. Apparently I also have none of these, or some or maybe only one of these, but not others. Every last one told me something that contradicted the diagnosis of previous psychiatrists. Whom do I trust? Nobody at this point, obviously.
If the professional themselves can't decide who has what mental illness, what hope have we plebs of ever knowing whether we're even mentally ill in the first place? Is it mental illness to be different? How different do you have to be to be considered mentally ill? Homosexuality was a mental illness in the not-at-all distant past. How can any of us trust what is not only a nascent and developing field, but more importantly, one based in division and hatred and stigma?
I am mentally ill because I cry almost every day, usually several times a day, without really knowing why sometimes. I am mentally ill because I hate myself. I am mentally ill because I want to die. And because I'm mentally ill, I am less of a person. I typically had no say in what treatment was administered to me, and under what circumstances. I don't steal, or aim to hurt others, but my house is most definitely the one that has seen the most police visits in the street (which I know is an eternal shame to my family). I am told that my lived experience is invalid, that the way I perceive reality is wrong and needs to be changed, needs to be fixed, because, again, I am mentally ill.
Am I mentally ill? I honestly don't know anymore. But it doesn't matter, because I certainly have no say in it. It has been decided for me that that is my identity and that is what I am, despite the underlying systems that define how a diagnosis of mental illness can even be made being completely, and utterly, and wholly, flawed, through and through.
