He may have to talk to someone on his own. In the meantime, hold on to the reality that he is split in half, of two very different minds. But one is potentially destructive. I am divorced 3 times, married 4 times. In my opinion, there is no such thing as a commitment junkie.
Commitment means sticking to it.
If you can't stick to it, you haven't really committed. My problem is I love too much. I have ten kids with eight different women. All I hear in sentences like that is a crippling struggle. You may be addicted to the rush of love, to the first year, the first six months, the 'honeymoon phase', but that's not the kind of commitment I'm talking about.