I'm going to out my friend to my parents
Why do you think that it is your place to out them?
I feel like my friend is taking advantage of me.
You shouldn't out people like that. You should not tell your friend's secrets.
He's a terrible guy, I have to let my parents know.
I think that you should let him say something when he is ready though. It is not okay to tell other people's secrets when they have nothing to do with you.