Should I stop our friendship?

I've been friends with this girl for 4 years (6th grade to 10th). She's a white conservative republican catholic girl who's very opinionated which I admire. I am a black protestant moderate/independent. I've always known that she can be very outspoken but now she seems to be going overboard for the past 2 years. Not to be disrespectful to any catholics but i just think what she does is unnecessary for salvation but the worst part is when she starts talking about how stupid protestants are or how idiotic democrats are. It's like she always has to be right. Like her way is the best and only way. She's very intolerant of people who are different and such a bigot! Today she asked me if i go to m on friday (good friday) and I said only catholics have m and she didn't know that. How can she expect me to know stuff about her culture if she knows squat about mine. Also, she talks very poorly of black people calling them ghetto (which some of them are) but I don't like how she generalizes like that. People have accused her of being racist but I'm black and her best friend. We're both honor students so we have a lot of cles together and it would be awkward if we stopped being friends. But she is really getting on my nerves and i stopped hanging with her outside of school for like 6 months. Our friends think she's a stuck up ***** but they're still nice to her like i am so id have to see her at birthday parties and dances. I don't know what to do.... Id really feel awkward telling her to wise up.....