How do you deal with women you don't want to get with, either because they're not attractive or they're dating/married to someone in your social circle?

What is your approach to keeping a good vibe, holding frame, and letting a girl save face when she's eye-fucking you or becoming touchy?

Also, what are good ways to be discreet with a girl in a relationship?

This is happening all the time as I progress on my redpill journey. I'd rather not become someone who cucks his own friends.