How hard would it be to reject a woman while drunk and still be loyal to your girlfriend/wife?

I saw this myself. My friend was trying to hit on a married man at a party. She was going for a kiss and started touching him. The man mildly shoved her and yelled ''Get Lost''. He did that while drunk himself. The man left earlier and his male cousin and brother drove him home.

Obviously she lacks some morals she's still a friend to me and I don't get involved too much in other people's relationships. I just watched and say nothing. She gets hit on many time (looks a lot younger than 29) and was surprised that man rejected her. I know alcohol lowers your inhibition but he still rejected her. How hard would that be? By nature, men are visual and very sexual. With alcohol, it would be usually easier for him to cheat.

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This is the first time my friend got told ''get lost''. It was a shock to her.
How hard would it be to reject a woman while drunk and still be loyal to your girlfriend/wife?
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