does facebook ever delete friends for you accidentally?

[Alyssa]

I recently became friends with someone on facebook, and we do talk in real life, so its not like we don't know each other. Literally we were friends like an hour ago and then I saw he deleted me because i clicked on his profile and it said "add as friend." We've messaged each other too a few times as well.
I don't think he would delete me, as I said, we are friends/talk to each other often in real life too.
Does facebook ever delete friends accidently? Or has my account been hacked?

[SB]

your friend deleted you because you suck