A very fair question. I've tried to give it some thought. I think what troubles me is the sheer obliviousness of it.
Oblivious to the pain you felt over the relationship crashing... .
The tough thing in all of these relationships is we all tend to be oblivious to the others pain - her husband, your wife, her parents treatment of her... . and of course, the devaluation and breakup of your relationship. And worse, pwBPD run away from their pain and shame... . it's too much to bare.
It's hard to deal with the fact that she is not processing this like you are... . especially when you both were so much on the same page for so long and how your feelings were so important to her at one time.
I struggled with this too. And I also realized that I have done the same to others in my life... . where I was on a completely different page - oblivious to their pain.
Maybe this is the hardest thing about someone leaving us. I remember this line in a Diana Krall song,
"there's always one to turn and walk away, And one who just wants to stay, But who said that love is always fair? And why should I care? ".
Love isn't always fair.
Was there something more I could have done?
Or was I not meant to be the one?
Where's the life I thought we would share?
And should I care?
And will someone else get more of you?
Will she go to sleep more sure of you?
Will she wake up knowing you're still there?
And why should I care?
There's always one to turn and walk away
And one who just wants to stay
But who said that love is always fair?
And why should I care?
Should I leave you alone here in the dark?
Holding my broken heart
While a promise still hangs in the air
Why should I care?