She's still boinkin him,
Get out, but before you do be sure to Eiffel tower her with the other guy.
Don't invest any money, time or emotions into this girl.
the "no feelings for" line when talking about someone's ex doesn't exist in the real world.
I go to war every time my wife considers spending time with another man (solo not so much in a group).
"MY MEAT, STAY AWAY FROM MY MEAT, BECAUSE IT'S MY MEAT!" Is my general rule of thumb, jealous? yeah maybe but what can I say, aren't we all just dumb cavemen when it all comes down to it?
Meat ?
No, we aren't all dumb cavemen about this, please don't try to justify your behaviour by trying to project it on other members of the male gender. I have known many women and men who were mature enough to still be friends after a breakup, especially when it was done on good terms and without kids, mortages or fooling around being involved.
Regarding OP, I don't think you are in the wrong if the ex doesn't want to see you and your girlfriend prefers ito stay this way. I have been buddies with some of my past girlfriend's ex boyfriends, but I have also shown the door to some who were still in love with the idea of getting their nose into the new relationship (ie. trying to cockblock me). Please to be seeing that tapping or sexual attraction had nothing to do with it, they jst wanted to make others feel miserable after their loss.
On the other hand, you sound hella insecure. As in, very much, and this translates into controlling behaviour. Do you really need to be around when your girl sees another man, even if it is another man that has already dipped his nachos in the grilled cheese ? Would you still find it appropriate if the girlfriend didn't
allow you to see other women when she wasn't around to check on you ?
If I were you, I'd start to think about cutting my losses, not that the girl is in the wrong, or whatever. Drama after 6 months never bodes well and yo are clearly uneasy about the ex still being around. Nothing wrong with admitting that. Plenty of other fishes in the ocean.