Another approach might be to attempt some behavior modification with him. That woukd mean no more getting on your knees to apologize. Instead, refuse to go nuts trying to smooth his ruffled feathers every time he gets unduly aggrieved over some perceived slight. He may have had parents who over placated him whenever he got upset as a child. That's a good way to create a little monster. You're basically following that same approach - tying yourself in knots anytime he gets his shorts in a twist.

It's like dealing with a kid who holds his breath whenever he doesn't get his way. Ignore it and he'll eventually breath. When he sulks because you've "offended" him, do this: Say - "I'm very sorry your feelings got hurt. It was not what I intended, and I hope you can forgive me." Then do absolutely nothing to molly coddle him. When he threatens to leave, or end the rekationship, say - "I wouldn't want you to go because I woukd miss you terribly, but it's up to you to do what you thing will make you happiest." Then absolutely say and do nothing to cater to his over-sensitive ego.

At some point he will ask why you are being so mean. Then say - "Any two people who live together are going to become annoyed or offended with each other from time to time. Grown up, mature people learn that they have to let things go and move on. If that's too hard for you to do, then you probably should go live by yourself." Then let him figure it out with no molly coddling. He will be in a crisis at that point. He won't want to stay because he feels he has to make you acknowlege that you wronged him and owe him reparation. On the other hand, he won't want to go because he doesn't really want to leave because he needs you so much, emotionally and otherwise. So he will be in a real dilemma. Resolving that dilemma or crisis without any molly coddling from you could lead to him becoming a teensy bit more mature.

That's what he should have had to do when he was a child. Instead someone started wet-nursing him the minute he got upset, so his brain is conditioned to need that. When I was a kid, my parents had a great response whenever my siblings or I would start complaining that we didn't think we were being treated right. They would say: "Well, if you don't like it here, there's the door." I'm afraid your boyfriend could have used a bit more tough love.