Is this is a pattern, since you say you've had "plenty of best friends"? Not having stable and long lasting close relationships is common with BPD. Especially if you get too close too fast because you might idealize people at first. Either way, if her behavior was consistently hurtful and mean, maybe a break is best. I'd just try not to focus on the hate and instead be more careful when making new friends. It's a good subject to being up in treatment (your patterns of connecting with people).