My mother-in-law has bipolar, and is in the hospital pretty much every spring. She has the benefit of being in Australia, where the health care system is leaps and bounds better than what we have in America, at least. I also have a friend who's worked in the mental ward of two hospitals.
Sure, when you're young, it's fun to go down the DSM and think about how some of the symptoms of schizoid personality disorder feel like they kind of apply to you, and there are so many self-diagnosed aspies on the internet, but this leads to anecdotal trivialization of serious mental illness.
Go volunteer in your local mental ward. Spend a few long months with diagnosed, treated (as well as they can be) mentally ill people. It'll change your perspective on so many things, from tragedies like this to views on trends in modern humor.
Almost as dismissive as summing up his post as, "I was like that, but fixed myself with Linkin Park."
I remember reading portions of a book on autism. (And before you ask, that was a real diagnosis from a real mental health professional.) Which had tons of statistics about people with autistic traits/on the spectrum. And I really wish I could source this, but the first chapter or such looked at what the chances of integration into society were without treatment. I think the number was either 1% or 10%. Either way the odds were stacked against you.
And so the thing that jumped out at me when I read that, was wondering what the difference is between someone who integrates, and someone who ends up in the institute. (I'm fairly sure the book was only covering HFA or Asperger's.) And the answer is: I've got no idea. "Wake up one day and 'cure yourself'." as the parent notes, probably isn't a repeatable strategy.
The point I take away is not the instantaneous nature of his insight but _what_ he realized: that the consequences of his vices would become more and more serious, and that he didn't want to pay the price. (The discovery of empathy, I think, was a side effect. People are generally emotionally blind to the side effects of behaviors they have no intention of stopping.)
I was confronted with facing my own ADHD a few years ago, which helped me stop making choices that were more comfortable in the moment but had suboptimal long term consequences. An example would be impulsively buying something on credit to make myself feel better, one of many little things I did to dig myself into a financial hole and, if I remember correctly, a very common ADHD thing to do. By opening my mind to the possibility that I had to face my issues, it opened the door to slowly chipping away at the core issue.
One thing to keep in mind is that mental health is a hard thing to work on. It takes several weeks in the best of cases just to figure out what's going on inside your head when working with a good mental health professional, and that's assuming your trying to get better and don't have ant major hang ups about being treated. Ask a psychologist at Kaiser Permanente, an HMO based here in California, how many sessions they can spend with most mental health patients. It's a very low number, something like 6 or 8 sessions.
Not only that, but some people, such as people with schizophrenic disorders, need medicine (Specifically, pharmaceuticals.) to stay sane, literally. Part of the problem with disorders where you need to take pills are that some people don't want to take them, or the pills help them, and then they decide they're fine and stop medicating themselves. At which point they relapse into an episode.
I think we absolutely need better mental health care, and better mental health care research. We still don't know much about basic things like sleep. And yet we're being tasked with treating a growing number of people with psychiatric issues. Naturally, the result is something of a disaster.
The stigma of mental illness often leaves people to think it's just something they have to want to overcome (or that they're not mentally ill at all but just need to overcome whatever problems they have) and there are plenty of people that will be happy to help them reinforce that terribly destructive belief.
But are a couple of problems with the mirror. One is that if you truly need to change, then really SEEING yourself is a traumatic experience, and like any trauma, it requires further care to make sure that it doesn't raise issues of its own. There's no way around this: the traumatic aspect of the mirror is what makes it a powerful tool for personal change. Another problem is the nigh-infinite variety in human psychology: different people need different mirrors, and while it might be possible to classify them broadly, what works for one person still might not work for another.
Put these together, and a major problem emerges with using the mirror therapeutically: namely, doing it in a humane manner. I truly don't think it's always possible to do this humanely; the grandparent's case had him seeing the consequences of his own act of cruelty, which implies that there was collateral damage. Another such case would be the reverse: someone who, like a puppy, can learn that biting hurts only by being bitten. That's someone who needs to experience a moment of cruelty from the opposite perspective, but that requires being cruel to the person. Clearly these are not cases where the mirror is humane.
But there are still open questions. Knowing the trauma that the mirror causes, can bringing it about deliberately ever be humane, even when the subject is not committing or experiencing cruelty? In cases where it can't -which might be all cases- might it be worth doing anyway?
As soon as you make the choice to either wrestle it into submission or surrender to it, you'll probably have an easier time. In this case it seems like taking charge.
Other people have no choice but to surrender and learn to live with the consequences. Maybe for you that means not having any sharp knives, or medication you can abuse, or alcohol in the house. We all have our issues. If we can't control them, we've got to mitigate them to the best of our ability.