You are right, a lot of us have had hard lives that have created circumstances and situations that contribute to our problems. I hope that your revelation is something that actually does help you.

However, I think that it would be wrong to dismiss the fact that mental illness is a real thing, regardless of cause and its not always possible to just "change things" to make everything all better. Many of us DO need medication and therapy and that's alright. We aren't weak, we aren't letting the people around us just convince us we have a problem and force us to remain mentally ill. Situational changes do often have a positive effect on a person, but situational changes aren't going to change the fact that I am bipolar. Or that someone else has DID. Wanting a new and happy life is wonderful, but not being able to just change our lives into this happy thing isn't something we should feel like we are a failure if we cannot do.

Like I said, I wish you luck and I hope this revelation makes you happy and things work out well. But your solution isn't a blanket solution and I would hate for people to have yet another reason to feel like they failed because they cannot just "change" their sucky life and magically become happy.