Learn this - Most people are afraid of confrontation. They try to avoid it at all costs. Reading your post, I assume that includes yourself. This includes most people at a bar, guys and girls. Alcohol can change things, but it is easy to defuse a drunk person.
I understand what you're saying. You start talking to a girl, a male friend of hers comes over and starts trouble. There are a couple paths you can take, some are wiser than others. You can immediately walk away - safe choice, she probably wasn't worth the effort anyways. You can continue to talk to her as you were - this will cause the instigator to get angry and either walk away himself or push harder. You can tell the girl to follow you someplace a little quieter and see what she says. Or, you can be billy-bad-ass and start an argument, which makes neither of you look good.
But let's be honest, this won't happen often. Like I said earlier, most people try to avoid getting into arguments. Even if the guy is twice your size, it doesn't mean he will automatically try to kill your chances. A lot of built guys have confidence issues, and are afraid to make themselves look bad.
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The hottest ginger you'll ever meet.
I don't have an ego, I just love how awesome I am.
