18. Behind My Back
In high school I discovered my best friend and my then-boyfriend were a thing behind my back. Ouch. I warned her because he was a total jerk, but she stayed with him. I moved on.
A while later, she calls me to tell me I was right, he’s a jerk and she’s sorry. I believe in forgiveness and friendship, so we put it behind us and maintained a very close friendship.
Until this year. We are now 15 years out of high school, and she is engaged to that very same guy. It happened quickly. They got back together in October/November 2017 and were engaged by December, then after lots of thought I decided that no friendship is worth having that negativity in my life.