Is this part of the struggle with having bpd? How does one go from in love and wanting to be life long partners to the next day wanting to break up bc the relationship is "fundamentally wrong" after a miscommunication that just spiraled out of control? 

I know no one here knows the details of the relationship but we have fun times and like all couples we have arguements. It just seems like the highs are high and the lows are low. I know it has more to do with working on emotional regulation during arguments but it's hard to hear and understand if we were building a life long partnership, why give up trying?