Obsessed with my friend’s wife

My friend is an average guy and got married into a really rich family. His wife is one of those social butterflies that can make a conversation with anyone and everyone and we hangout often. I never had any feelings for her initially but one time she was in my car and left a coffee cup with her lipstick stain on it. For some reason that turned me on and I licked the shit out of it (before you judge, I am a creepy guy).

They are both very close to me so she tells me whenever they fight and I try to be a good friend but deep down, I badly want to give her what she needs. I can barely hold a conversation with her now. I keep staring at her lips when we talk, check out her ass, came in her underwear mane times when I was at his house and I feel like I’m losing control. I don’t know if she’s leading me on but she always sits next to me instead of him, playfully pats on my thigh, asks her husband if she can ride with me (I have a fancy sports car). We both make fun of my friend together by calling him a loser.

Please help, I need advice and not a moral one (I know the right thing to do in a bro code is to respect and walk away)