I was dating someone at the time who had just cheated on me and met him through a mutual friend. During a night of heavy drinking he kissed me and I let him. I told my boyfriend at the time, but we all still hung out together two nights later. That night, I knew it wasn’t just a one night thing when we held hands and it felt so natural. More ended up occurring and I didn’t even regret it one bit. Afterward, we knew it had to be discussed, and ended up talking nonstop for hours.
Postscript: I quickly ditched the cheater and have been incredibly happy with my new guy ever since.