I didn't recommend leaving him, Blueberry, I asked you to speculate about couple of inspiring actions you
could take in breaking the pattern that you are in. Leaving him would, of course be one such action, but only you can find inspired action to break your own pattern. That the first thing you think of in reply is leaving him says something about what's at the forefront of your mind, now, doesn't it?
One thing I want to point out, Blueberry: assuming responsibility for the well-being of another adult is the ULTIMATE in controlling behavior. To think that another grown-up would not survive your loss!! That's about as arrogant as it gets. Well, you can hold onto that belief if you want to, but it's not going to do your relationship any good, whether you stay or leave.