You've unloaded a lot, and no doubt you have been through a lot. A lot of us have experienced PTSD and I get the sense that you have been through a lot of trauma. If you haven't done so, maybe explore that aspect? In terms of stuttering a big eye opener for me was I have to stop defining success by connecting it with a fluent moment. When I disconnected the two, it was a lot easier for me to get out of my comfort zone. That's when life began for me. Start small. Even if it's just stuttering on purpose by yourself.