Ex keeps coming back and leaving?

Anonymous
We had 4 years together, known each other for 10 and broke up this past summer.
We promised each other to be friends but whenever he finds someone else or a new group of friends (he never stays with one group for long) he starts putting me on backburner, saying he loves me but will go through phases where he'll not pick up my call or couple texts I send. I also do a lot of him (he asks for my help) and usually recieve no thank you or a very late text, like the next day. Then he'll usually call a week later like nothing happened.
But if I don't respond right away or if I hang out with another guy, his world ends.

Because of this I told him I can't sleep with him anymore because it causes me grief. I don't want to tie him down and him be unhappy, but I still have deep love for him and the way he treats me, really throws my day out of whack.
Everytime I say I won't sleep with him anymore cos of this he goes into wooing me, just saying sweet things to me and hugging me close. I suspect he's just trying to use me as a security blanket until he finds something or someone better. He constantly talks about other girls with his friends from an outing that I wasn't a part of and girls always text him (of course he's contributing) and when those girls are around they're very mean to me. Just last week he said I can't come out with him anymore because none of them like me. Some even refused to get in the car to hang out cos I was there.

What realy distresses me also is that his parents call me looking for him and this is usually when he's ignoring me. The horrible thing too is that I'm also dating someone else who treats me so much better. We're not actual boyfriend/girlfriend, but he's deployed so I guess I'm just lonely.
I don't know what I got myself into.
Ex keeps coming back and leaving?
2 Opinion