If you don't want to be in the friend zone, stop being their friend.
Being a "nice guy" is bullshit, so throw that right out the window. I'm not saying be an asshole, but the reason why you are being put in the "friend zone" is you are trying to be buddy buddy with them in order to get laid. First, that's not effective AT ALL and second, it's immoral.
Hiding your intentions is the same as lying.
I'm not saying walk up and say, "You're hot, wanna fuck?" but don't be their shoulder to cry on and don't act like them showing you attention is a favor. Flirt, make eye contact, have a strong presence and make moves to advance in a sexual and NON friendly way.
Sure, they may reject you, but it's better than listening to them whine for hours about their ex.
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