I really don't understand why is it such a big deal. You know that you are not the only woman on this planet, right? He will from time to time look at other women, be it strippers, woman on a street, co-worker......and it's normal. As long as it's "looking and not touching" it's ok.
Tell him you have a problem with it but don't try to stop him from having a night out with guys. It will just come back to bite you in the ass. Years down the road when you are arguing over something stupid he will throw it in your face. At least if you let him have BP YOU can be the one doing the "throwing" in the face thing.
But seriously, it's really not a big deal. Just get over it and don't let one night stand in your way of happiness.