You've hit the age when adult responsibilities kick in. That can often trigger a breakdown. It happened to me. Just when we've finally mastered a lot of what it takes to live successfully as a youth, we are thrown into the demands of adulthood. Maybe the military served as somewhat as a cushion. While you were in it, a lot of choices were made for you. Now - you are really your own person. That's hard.

It's not normal, IMO, to be mentally ill. Despite what doctors may tell us, I think a lot of us who have been called mentally ill may really be more along the lines of emotionally distressed. Everyone and their dog is getting diagnosed as bipolar these days. I'm skeptical of it. There is something that you need that you are not getting. That's my opinion. Socially, you are not meshing with other people. I base that only on what you are saying. (Plus, I think that's the basis of most mental distress.) Somehow, you have to figure out how to connect successfully. That can be terribly hard. But, if you had success in the past, as you say you have, then you have reason for hope.

You have to go out of your way to leave the computer and spend time with people whom you are not paying. That's the only way to learn how to live life. Easier said than done. (I sit here with the computer, when I should go out more, too.)