I agree, you're not rambling. And I know how disheartening it is, having to continuously deal with mania, depression, psychosis... Not to mention the effect all that has on your confidence and faith in yourself and your life. I do hope you're not having to deal with that on your own. Do you have a therapist who can support you in this?

I think being a special ed teacher is a beautiful pursuit. If that's what you love, I think you should at least try going for it. Don't give up on yourself before giving yourself a chance, at least that's my opinion. In the worst case you'll have to quit, but it's never too late for that. On the other hand, you might succeed! In the meantime, all you can do is try to enjoy the process as best you can, and take all the support you can get to help maximize your chances.