it's the black and white thinking that's all part and parcel of BPD.
that is exactly why you hold a grudge for so long. once someone has crossed to the other side you have trouble getting them out of there. are you able to be pleasent with the person when you are around them? if you had good times with the person think about that instead of what they did to you. work on acceptance that they did that and there is nothing you can do about it but hating them doesnt make a difference. hate is a poison, and it is actually very harmful for your health. just learn to say f*ck em, and then stop caring or thinking about the person all together. If they hurt you really bad, why are they even important enough for your hatred? they shouldnt be in your thoughts in any way shape or form, but if you want a relationship with them again, then think of the good times and move on from the bad times, accept that there is bad times and let them pass by, dont try and hold onto them.
"A question that sometimes drives me hazy; am I or are the others crazy?" Albert Einstein