Past relationships

I just got finished speaking with a girl I haven't spoken to in 13 years. She used to be one of my closest friends and roommates but we both ruined it the night we slept together. We were drunk and experimenting. The night was great it's just I felt different the next day. I felt that I did something wrong. She was fine. We both had boyfriends at the time.  I eventually just moved out bc of the awkwardness in the house. I never spoke with her again until this morning. I am not going to lie. I have thought about her over the years. She has been in several of my wet dreams and fantasies. Then this morning I noticed her brother on Facebook. I friended him and saw she also sent me a friend request. It look like it was sent a while ago but I just didn't see it. I friended her. (No hard feelings my way) then came the IM's. We spoke for 20 minutes just catching up. I did not know she still lived in town. She said she knew I was pregnant from seeing my Facebook posts online. Basically long story short... We are planning on getting together for lunch one day soon. We are both pretending that night did not happen. But we both know clearly it did. How long before one of us brings it up? It's going to happen. I am not going to Persue anything. She is married. I have a fiancé. We will see where this goes. TO BE CONTINUED...