I slept with my best friend who has a partner and now we don’t know what to do

I, (20F) slept with my best friend, (21F) and now we don’t know what to do. She has a partner, who has cheated once, so she has a “free pass” kind of thing. The relationship is long distance, and my friend is content. A couple days ago, we drank a lot and I ended up sleeping with her. We have two options: 1: pretend like nothing happened, never do it again and hope we don’t mess up the friendship (safest option) 2: pursue the relationship and also risk the friendship (we both like each other)

We also LIVE together. We have conjoined severe anxiety over this situation, no one to talk to, and are coming to reddit for advice. We are assholes. We know this.