How do I tell her I think she has BPD

[Caboose]

I met someone very special in the fall of 2015 and I believe at this point (April 2017) we are heading for a break up. About 6 months into the relationship, I began spending a lot of time trying to figure out how something that was completely benign to me (me: "yes, you've seemed a little stressed today." (no sarcasm, completely loving tone) became a three hour argument.) These arguments became more frequent, lasting longer and longer, and I began saying, "You are arguing AT me. I'm not really participating because I have no idea what the argument is about." A friend suggested the possibility of BPD so I bought "Walking on Eggshells" then "Walking on Eggshells Workbook." In the workbook I took the ":)oes your person have BPD?" quiz. As you probably know, if you score >20, it's likely the person you were thinking about has BPD. I scored 37!. Everything I read about BPD fits except the self harm - cutting or suicidal threats. As far as I know, those don't happen. All this narrative is to demonstrate I really, really think she has BPD and I would like to tell her. I don't think we can save the relationship at this point, but I need to tell her an I don't know how to even begin that process. Any advice extremely appreciated.  Thanks! 

[RELATIONSHIP PROBLEM SOLVING]

RELATIONSHIP PROBLEM SOLVING This is a high level discussion board for solving ongoing, day-to-day relationship conflicts. Members are welcomed to express frustration but must seek constructive solutions to problems. This is not a place for relationship "stay" or "leave" discussions. Please read the specific guidelines for this group.

[Naughty Nibbler]

Welcome Caboose:   
I'm sorry you are having trouble with your partner.  Telling someone you think they have BPD generally doesn't go well.  The best thing you can do is to deal with the specific problems. 

These arguments became more frequent, lasting longer and longer, and I began saying, "You are arguing AT me. I'm not really participating because I have no idea what the argument is about.

Check out the links below.  The information should be helpful in regard to the arguments.  It generally takes two to carry on an argument.  If you set some boundaries, take a time out and don't engage in circular arguments, it can make things better for you.  If she keeps arguing with herself, you have to remove yourself from the situation.

BOUNDARIES

ARGUING - DON'T ENGAGE

DON'T JADE (Justify, Argue, Defend or Explain) and avoid circular arguments

TAKING A TIME OUT

You can't change her.  The only thing you have power over is yourself.  You can control how you interact with her and how you react to her.  Give the above strategy a try and let us know how it goes.  There are links to more lessons in the right-hand margin.  Take it a step at a time.  Sometimes, when one person in the relationship can make some changes towards using an emotionally intelligent strategy, it can make a difference (even if the other person is still being emotionally immature ).