Some1sAngel...
what to do in your situation you ask..something only you can really determine, as you probably already know (and my have been only a rhetorical comment on your part). I do deal with a somewhat similar set of cirumstances, but definitely similar questions.....guy back from Iraq, " two (or more) people"...care about him a lot but his actions and words are very confusing and disturbing at times...how to be there for him but not go crazy myself etc etc.
Differing from your situation is that he and I broke up soon after his redeployment (a year and a half ago he redeployed)...I initiated it, but his actions played a huge part (or lack of). To this day, we care about each other very much, but as time has progressed his PTSD seems much more pronounced. I can only say that right now I'm glad he doesn't live in the same State as me as I find that who he is now - 'different people', often angry and stressed' can be more than I can take on a regular basis.
But...as I said before, I care about him a lot...so am plagued with similar questions as you, at times.
Right now, I'm learning that I can't handle too much of it and that I have to create boundaries, which consist mostly of me not reaching out to him but ever so sparingly and still allowing him to call, if he chooses, which is not often these days. Also, not obsessing about how he is doing etc and letting go...SO hard, that last part, as I feel like a 'bad person' for doing so...I worry about him....but if I don't let go I will suffer and that doesn't help him or me. this is much easier written than done..but I find when I do it, I'm much more peaceful.
So I share all this with you to show that others, such as myself, are in similar situations (not exact, but close) and that there isn't a definite answer on what you should do, but there is some definition on self-care, and that it's ok to put yourself first, even if it means some letting go, however you define that. Take care of yourself and how you feel...are you happy with how things are, right now? Or are you holding on to what could be, what he once was etc? I wasn't happy, so had to make space, but I've not left his life and have still loved him, and cared for him as a very good friend. I deal with worrying about him now, deal with his anger (sometimes) and can only imagine what it would be like if we were an actual couple. I don't think I could handle it (him), not the way he is right now.
best to you ~