I will start, since this was my idea.

Dear You,

I know it was wrong to sleep with your boyfriend.

In my defense, you also had a girlfriend. You had plenty of lovers to go around.

My mother had just died, a month before. My mind wasn't in a place where it could think about friendship in the way it was meant to be thought about.

In my mind, I learned from you how to treat my mother the wrong way, and It was something I couldn't forgive you for. I couldn't stand looking at you.

I had to do the only thing I knew how to. Wreck everything.

If I could undo it, I would. But since I can't, this apology that I will never send to you will have to do.

I'm sorry I ruined our friendship over my irrational moment of inclarity. It was myself I needed to forgive, not you.

Love, Me