why are alot of white ppl racists?

Im not saying all the are of course. Im a black girl and to start off im not one of those ppl who always say 'is it because im black?' But i have a friend who is kinda racist she doesnt like anything that has to do with blacks. Boys, music etc. And she kinda generalize the whole race and not just black like asain and stuff to. She makes jokes about them. Also she doesnt like being in places with alot of black ppl and when we walk by them she always gets uncomfortable. And she thinks racist things like black ppl dnt wash thier hair. And when we were in the store today i picked up a tube of lotion and shes like ' dny take that that belongs to the store' like i was going to steal it. Also she alwsys thinks im using her for money. Im srry that was alot but its bothering me u know. It makes me mad because I'm getting older and I'm figuring out how the world really is towards people. So should i keep being frnds with her or talk to her about it?