Aaah man, I feel for you so much . Just reading what you're saying causes a sinking feeling in the pit of my stomach when I try to put myself in your shoes. That's got to be the worst thing when that happens, because you know there's not much you can do about it. If you do something, she thinks you're being insecure, the guy thinks to himself "Hah, this guy is weak, they're gonna fight about this tonight, hah, she shouldn't be too hard to grab away from him!" and your girl thinks you're weak too if you act out in front of that guy, and she resents you. This hurts on so many levels. Girls just don't get it, they never will. I know how you feel, we know how guys think because we are guys, I'm sure you know what I'm talking about. There's always that guy somewhere in the damn supermarket or ice-cream shop or wherever that's making eyes at your girl. He's always some low-life jackass slacker who sucks *** big time in our eyes, but somehow has always got ALL the women gawking for some crazy reason, because he's got like boyish charm or looks or cool clothes or some crap like that. You see, we as guys know what they're all about, they are professional girlfriend snatchers who hang around in places to see how many taken women they can wrap up for the day. I never like these guys because they've always got everything on their side, if you moan and confront him, you're girlfriend hates you because she feels embarrassed about you being jealous, if you do nothing, he charms the pants off her and takes her away. Either way he causes a rift between you two. So, the only way to deal with these a**holes is to establish your manliness on your woman in front of him. You take her right there in the damn shop and you plant a good one on her, and she'll say "What you're doing, people are looking!" and you say "Baby, you just wait till we get home!" and say it so that he can hear it. He for sure won't be able to make a comeback after that. It's such a pity you have to resort to this, it is kind of embarrassing, but the jackoff asked for it when he messed with your woman. She will actually like it in her mind, even if she'll never admit it. I think women like it when guys get in a tussle over them, but more so when their guy defends them against charms of another in a cool and manly, yet non-insecure or non-jealous way.

The simplest way to put this is you must show that guy that you are so good (in the eye's of your girl) that you don't even consider him a threat at all, but at the same time you let him know that she's yours and he must back off. It's a confidence thing, even if you've got to fake it. Just don't cause a negative scene, that's always the worst thing as it can drive your girl away from you too.