This anxiety and racing thoughts are the worst! In the morning they hit hardest (for me, that was when I was most likely to feel like hurting myself. The sunrise was "Oh no! Another day!"). Don't forget to check your thyroid (just saying).
Totally my opinion.
There is a pretty big step for a husband to go from frustrated with his wife, to leaving her. Leaving is not such a casual thing for someone who has chosen to get married, depending on the marriage. Marriage makes the love, love doesn't make the marriage (IMO if it was a quick marriage, after a brief courtship that originated in a nightclub/eharmony etc., I would worry). Strictly opinion by the way.
Being on medication since 14, chances are, he had some idea who he was marrying, and loved you the way you were. In the long run, marriages run hot and cold for varying years without ending in divorce.
I really don't see the problem with taking medications. Taking medications, for some of us who are mentally ill, IS dealing with our emotions. I do, and my wife appreciates it. Even the antianxiety medications (very seldom now) regardless of the propaganda about them being dangerous . Maybe ease back on them as you got off them. Maybe you don't need as high a dose.
There are local programs that he can attend Saturday mornings by himself to learn about individuals struggling with anxiety and mood disorders (Family to Family for instance). My wife went to them. Males, also, like to help, even though they act annoyed, at first. For me, when my wife gets emotional, I shut down also. Sometimes I think "I am not the one who is going to ultimately fix this." but I don't think "I'm tired of this, I'm getting a divorce!"
Anxiety creates its own PTSD (oh no! Here it comes again!! Type experiences). Anxiety brings depression. The memories of our mental breakdowns are traumatic in themselves. It's hard for unaffected people to imagine that death is an improvement, but for our tormented minds it seems to make sense. Your worry about losing it some day and not being cared for are very very common thoughts for those of us who struggle with anxiety, but it will NEVER happen.
Communication may be good, but for me it didn't work. It seemed the less I talked about it with my wife, the better it got. God is not going to let you fall in the least. You are cared for, and it sounds like you are wife worth fighting for. Us guys are very emotionally dense. We may care deeply, but only let out a couple of grunts to express it, sad to say.
I threw out a lot of opinion, so I may have completely missed the point.