You don't seem to understand that your post suggests that it is all growli's fault that she has a hard time with friends, and what I'm trying to tell you is that her strong reactions have to do with things that are not under her control entirely at the moment. Going to therapy is the main thing that is going to help her with that. Her problem is not that she's a *****, but the fact that she lives in a world of people who are less emotionally sensitive than her, and that her sensitivity was aggravated by all the abuse that she endured. Therapy is really the only thing that is going to help her navigate her sensitivity.

The point is that it is just flat out invalidating to suggest that someone has no friends because of the way that they are (this implies that the person has no worth as they portray themselves at the moment). It is clear from other things Growli wrote here that her friends may not have been the most understanding kinds of people. I expect that friendships will always be difficult for people with BPD because being more sensitive to things in general is a very alienating experience. And while it might be helpful for you to just know out right that you are doing xyz thing, you can't assume that is what is best for another person. You might consider the other person's personality before you decide that "tough love" is really the best thing. People with BPD tend to be very self critical and hearing criticism of one's person from the outside can cause a very intense emotional reaction (most likely shame) if the person does not have the skills to deal with it.

And as far as the empathy goes, I cannot see any compelling reason to empathize with someone who doesn't seem to be under emotional stress at the moment.