Your guy sounds like my husband. My husband isn't a jerk, he's just very selfish and self-centered. Claimed to commit to me when it was convenient for him (i.e., when he was afraid I'd leave him), but never truly committed. 30+ years later....

There's something SERIOUSLY wrong with men who cannot commit. My experience tells me that the reason your guy is still attached to his ex is because he can't stand the thought of losing control of her. Try telling him you're leaving him and no longer want him in your life & see what he does. Betcha he'll *suddenly commit*. Until he wins you back. Then he'll distance himself again.

I call these men "harem gatherers".