My step-dad was a lot like this when I lived with him and my mother. He said exactly the kinda thing your dad said to you but my mother always assured me that it was just because he didn't understand.

Close to the time I was going through the process of moving out, something triggered inside of me and I was upset and angry and just... "bleurgh". My mother got upset and my brother got angry and it was a very heated situation. Once I'd calmed down and had a good little cry (manly, I know) my mother told me something that shocked me: he'd actually said to my mother "Don't worry, it's just his condition".

Like WOW. Where the heck did that come from?!

So yeah, it's probably more the fact that he doesn't know what to do or say. Dads are like that. When I first started self-harming my actual dad grabbed me by the arm and raved on about how I should be locked up in a hospital and this and that. I was sent to my dad's spare bedroom, where I slept at his, and received a barrage of abuse for the next couple of months. Eventually he came around and started to understand a bit more but he still doesn't QUITE get it. He still asks me every now and then something like: "So that Bipolar thingy is fixed now?" I can't get it through to him that it's not curable but treatable. Oh well, I know he loves me nonetheless.

Have you got a psych team or anything like that? If not then get in touch with one and get yourself a support network set up. Then ask them to explain to him - it could help. Or you could maybe send him a link or two to some information about your disorder or print a leaflet of some kind out and give that to him

You'll both get there eventually. It's a learning curve for all involved.