'27M' Tormented with guilt and lust simultaneously cause of friends sister in law '29F'. Unable to think straight and how to act. Any advice?

Its about a tinder hookup. she was on my bed within two hours of match which is pretty rare here in india. she was leaving for hometown for her marriage in two days so pretty much surrendered to me completely. that was my first experience where i got to go insanely wild and tried everything i thought of till then. twist here is she married my close friends brother which i got to know after their marriage. i met her in family setting multiple times and it always feels like iam seeing her naked irrespective of what she's wearing. its been long time and we never spoke about it and i haven't told my friend about any of this. I can't get over her and what we did that night. I might have forgotten about her but as i am meeting her often its like a constant reminder. On the other my friend's brother is a very introverted and soft spoken guy who was always kind and helpful to me. I feel like i should tell him about what happened but when i see her I just feel like banging her again.

TLDR: Tinder match to bed to close friend's sister in law. Trapped in a cycle of desire to take on her once again and to come clean infront of my friend's brother.