Thank you for your kind replies, guys!

I have a therapist that helps me with my anxiety and I've been seeing her for a year now, I'll ask her if she thinks it's alright to confront my dad in a session. I might chicken out though...

I like the idea of writing a letter, but should I give it to him? I know an abuser won't take responsability for what he did, but I want him to know how bad he hurt me... and at the same time I don't want to be too agressive either.

Thank you, guys, really. Knowing what happened was awful, but at least I now know it did happen and I'll try my best to get better.