I'll try not to sound like a school kid here.
Is your Ex really hot?
Is your Ex a rambunctious lady?
Is she one of those people you just can't get along with, but her attitude and way of things is something that turns you on?
I'm only 23, but I've been in my fair amount of relationships, but I feel I can possibly help here because I have so many friends in their late 20's and early 30's.
I have found alot of my older friends to be in shambles in their love lives.
They have the responsibility of children, and yet act like one!
Most of them have one thing in common.
They want to be kids again relationship wise.
They want a hot, loud girl they can show off to all of friends or not-so friends.
It's like high school but in your 30's.
Knowone wants to sell themselves short, but alot of men feel that way about their women.
It sounds to me( I mean this in the best way) you need to GROW UP!!! I understand that it sucks having an old flame with another guy, but dude, your married again!
It's sounds like you could never make it work with your EX, and THAT'S what keeps you coming back, the challenge itself is the attraction (that and wild sex).
How could you marry another and still feel this way?
How could you NOT talk to your current wife about this? She deserves AT LEAST that.
You have some soul searchin to do buddy, and it's not another women, it's yourself.
Edited to add, most not all, of the guys I know that fall into this catigory love Porn and titty bars with a passion, which further complicates things due to adding to the already lack of respect for women.