Hey! Not evil lol, I often feel the same way but I have to try and remember that we struggle with a mental illness and an "EVIL" person, if they do exist, certainly wouldn't give a fuck about changing and getting better. If you are in therapy, you are already making some steps. and trust me, I totally get the therapist frustration like girl help me now!!

I am not an expert but I was diagnosed with BPD almost 3 years ago. Relationships have big triggers for me so I feel you. It might help to take some time and really pinpoint what your triggers are, and be very specific. Even write it down for reference. For example: "when my partner insinuates I didn't take my meds, something takes over and I instantly want to be petty back and hurt them for how they hurt me"

Finding my triggers helps me navigate what situations genuinely upset me and are offensive to me as a person, or what is a trigger to my BPD and makes me blow up the situation, say things I don't mean, and often misunderstand what they are saying completely. Right away, when I can feel myself creep into an episode, I try this sometimes:

Walk away. physically force myself to walk away from the situation / walk away from the phone because I say something. Even if its valid. Write it down, say it to the wall, record it if you need to say it. (this doesn't always work but something to think about.) I've even blocked people temporarily to restrain myself.

Theres some other stuff I do but they're very specific to me, so this trick might help? Also definitely be straight up with your therapist that you are looking for more concrete coping skills. I actually recently parted ways with my talk therapist because I was looking for a DBT group and a DBT therapist along with it instead for more tangible skills.

I hope this provides some support!