Another blokes perspective on this:
The fella sounds like he has even more self-esteem issues thatn you. He appears massively insecure, and propbably hates himself for doing this to you. I can imagine that he has been hurt badly in the past and doesn't want it happening again.
However, none of these are your problems. Until he can sort himself out then he shouldn't be trying to start new relationships. A wise man once said "You can't be with someone until you can be on your own." What he means is that until he has proved to himself that he's in a relationship through want rather than need, he's going to have these issues.
From your perspective, I would walk away. Maybe in the future, whatever attracted you to him will still be there, maybe not. But right now he will drag the pair of you down, till there is no love just anger and dependance.