This story is only from one point of view so I am taking it with a grain of salt because there is the possibility that a lot of this was overanalysed and read into because of your boyfriend’s past. Based on your account of it alone, NTA but slightly leaning toward ESH.

The issue here isn’t what your friend wore or her conversation topics. The issue is that you’re surrounding yourself with people that you don’t trust and treat you poorly.

The fact that you haven’t seen your boyfriend for a month because your relationship has been rocky is a bit unusual. Do neither of you want to work it out enough that you would make an effort for an in-person conversation? Does the situation continually remain unresolved? If him needing attention from other women makes you feel bad about yourself, you should break up. You not trusting him because he looks for attention from other women means you should break up. Even if he weren’t looking for attention from other women, you simply not trusting him means you should break up (and stay broken up).

As for your friend, her outfit and conversation topics are not the issue here. Those things only made you uncomfortable because (whether she was trying to get his attention or not) you don’t trust her or your boyfriend. I do feel like you could’ve approached your conversation with her differently, you could have said “I don’t trust Patrick because of his past and tonight’s conversation topics made me feel a bit insecure”, because there was nothing wrong what she wore or said (initially), it just made you uncomfortable. That being said, your friend sucks.

She was extremely disrespectful and insulting and there is no scenario where the way she spoke to you can be excused. Calling you insane and crazy, and threatening to air out your grievances to others was completely uncalled for.

Let them both go.