Starsky, have you read/researched anything about the psychology of that? Because I just don't get it. That seems like childish behavior to me: "I don't want you, but I don't want anyone else to have you, either." Why is he like that when he's the one who left? He's the one who said if he came back now and went to therapy it would be "only out of convenience." He's the one who chose someone else over me. So why does he CARE? Seems he'd be indifferent and would actually WANT me to move on so I'd be out of his and OW's hair once and for all! RIGHT???
Oh, my poor dear Train, you women sure do crack me up. You try to make us men soooo COMPLICATED, and we really are quite SIMPLE creatures.
It's simple "push/pull" dynamics of male-female relationships, with some male "tagging" thrown in for good measure. (think peeing to make your territory)
Men are horny, competitive, horny, territorial, horny, stubborn, competitive horny creatures. Look up Occum's Razor and you will have your answer.
You try to make us men soooo COMPLICATED, and we really are quite SIMPLE creatures. 
