I have bipolar disorder and I don't act like that - but I have been stabilized for an extended period. Some people with bipolar can act rude, moody, etc if they are in a mood episode. Some have their tempers flare up. This is all temporary if a person is following a treatment plan.

Episodes last for extended periods, typically. Weeks, months. If she's flipping out on you one day and totally normal shortly thereafter then that doesn't sound bipolar-related.

Your friend certainly has established quite a pattern. Maybe give her one more chance like the above poster suggested. But that's it. She may just be a person that isn't a good friend, period. She may be a mean-spirited person that uses her illness as an excuse for bad behavior.

Good luck!