Horribly knotty hair help

So, I've always gotten tangles, I have a lot of VERY fine fair, dead straight. But recently the knots have been unbearable. I brush my hair when it's wet before I blow dry or air dry. Every brush stroke creates more knots. Idk what to do, I've never experienced this before. I have EXTREMELY oily hair, so I would prefer not to use an oil, but does anyone have and product recommendations? This morning I but my hair in a bun and it's just a knotted mess, but I didn't have time to mess with it anymore. And it hurts. Which is great. Also, I need a haircut pretty bad which I know will help, but until then...

Also, absolutely no Monat, disgusting company with products known for hair loss ans scalp scalding. Not interested in that.