When I look back at my pre-medication days, it was the case that my bipolar worsened as I got older. Like Nammu, my 30s were full of psych hospitalizations. I even sometimes call it my "lost decade". I was obviously on medications for most of those years, but factors prevented them from stabilizing me. These included, I think, how bad my bipolar was at the time, my fiddling around with and/or stopping meds, drinking, and the continued stress I was under. I'm also a believer in the "kindling effect" for illnesses like epilepsy, bipolar disorder, and migraines. This effect made my illness worsen and hard to treat for a while. However, I did eventually stabilize. There's been no worsening for a while.

I'm sorry you've gone through so much for so long. Your experiences sure are classic bipolar. I even know what you mean about some seeming like DID. My guess is that the kindling effect is part of your struggle, but you can calm and then end that tendency. It's not easy, but it happens if it isn't stoked, you're on a good med mix, and using various positive coping tools. When the first (especially) and last mentioned, even meds started to become more effective for me.