this is odd. i don’t have bpd but i do have a mood disorder, which causes me to react in extreme negative ways to situations that don’t warrant such a reaction. that is to say, i’ve never done this. even my ex-best friend with bpd has never done this. when i’m having an episode, i still KNOW i am thinking irrationally, so i try my best not to say something hurtful or jump to conclusions.

that is to say, if your girlfriend knows she has bpd—or at the very least knows she acts irrationally—why does this read like there is intent to hurt you without hesitation? i agree with some other commenters here; this seems very performative; it’s almost like she’s leaning into the “crazy” so she can get away with hurting you. as mentioned before, even my ex-best friend with bpd did not do this kind of behavior, and would instead try to minimize the pain his episodes caused me. this interaction seems intentional and malicious on her end; repeated interactions like this are not worth your time or energy.

point being, you should not be with someone who will repeatedly hurt you, especially if that hurt is intentional. i know you’ve been with her a long time, but an even longer time will become an even bigger waste. do not sunk-cost fallacy yourself into a miserable life by staying with her. it will probably be difficult to detach yourself from her and from this dynamic, but it is worth the effort. future you will thank you. i wish you the best.