I have had a male best friend for the last 5 years who always was in love with me.
I didn't love him in a romantic way and have found a partner in that time.

So I am in a relationship and my best (and only) friend has found a girl and is starting to fall in love with her.

While I am happy for him, in the little part of my normal brain, I hate him for leaving me. It feels like a heartbreak. I can't stand it.
I cried and sobbed and felt alone ... while lying next to my partner.

I hate myself.