I feel awful

So a long time ago I met a guy. We became friends instantly and it their was never an attraction we just kept it as friends. A year after I met his brother and his brother and I started something that lasted over 5 years. Me and his brother are now NOT together. And I’ve been single for a while. Me and my friend stayed best friends through it all. Breakups and make ups. Never nothing until about 3 weeks ago.. we went out and got drunk with some mutual friends for our friends birthday party.. anyways it was probably the alcohol but we shared a kiss.. and it wasn’t a sexual kiss at all. The next day I msgd him about it and he apologized as so did I.. we tried to move pass it and it was stuck in our heads. We both have shared so many talks about being truthful so I was the one who initiated the whole conversation into detailed. We agreed to dig more into it and it happened.. (we had sex) now I know what most people are going to think. And honestly I don’t judge you guys for saying what a whore!! But it didn’t feel like just sex between us. We’ve been secretly talking about how beautiful all of that was.. and how great it felt to have done it with each other, (not the sex) but how we were after it happened. We went out, talked about the past and future. Something we would always do. Nothing happened it was just a day spent with my best friend again. We both agree that it’s something that it’s never going to happen, not in a serious matter anyway.. we know each others family for more than 10 years.. and we’re afraid to get judged.. I’m not sure why I’m writing this. I guess letting it all out feels better than to keep everything inside..