My Neighbor 'Went There" At A Neighborhood Pool Party - I'm Happily Married But Got Propositioned

We live in a nice neighborhood where there isn't a house under 1 million. Anyway my next door neighbor us away on holiday this summer and his niece and nephew are staying at his house next to me. Long story short one of our cul de sac neighbors had a pool party. My next door neighbor's nephew Mark is a 30 year old athlete. A swimmer. I'm a 52 year old out of shape married guy. Well we were all drunk at this party and I went inside to use the bathroom. It was locked and someone was using it. The toilet flushes and Mark comes out in his speedos. I say hi as he walks out and Mark being drunk tries to kiss me!!. I'm like whoa Mark!! Wtf are you doing! His speech was slurred but he says Mr. Smith I've always wanted you. Then stumbles back out to tbe party.

Never had a gay thought in my head up until after that. My wife has gotten fat and out if shape. Meanwhile Mark is in perfect shape and had an amazing physique. I'm not gay but my mind won't stop thinking about letting Mark at least give me a BJ. I feel totally guilty about it and I know it's wrong. But the thoughts keep coming.