I'm so sorry that you are feeling so terrible right now

You are not a failure because you are not ready to go back to school yet. Obviously you are deeply depressed and suffer from significant issues with anxiety. I'm sure that was a barrier to your success, that's why you were so overwhelmed, and that's not something that you can control

If you feel like you may hurt yourself, and you feel like you should go back to the hospital, you should go

I have had to voluntarily commit myself before. It wasn't easy, and it was the last place I wanted to go, but I knew I had to be in a safe place and needed more intensive help to get better.

I have also often felt like a burden to others, and frequently feel isolated and alone. They aren't easy feelings to deal with because it's difficult to always feel independent when you have medical problems, and it's not easy to meet friends when you get older.
I miss working, and contributing, but I try to focus on the things I can do even though that's hard sometimes. And this forum has been a Godsend for me over the years. We are a small group now, but we are like a family.

I'm spiritual, but don't believe in organized religion, so I can't turn to God for comfort like some other people can either