No you don't have to be "bitter" even if you have pain in your life.
I think a lot of people become bitter because they don't work on themselves and heal their pain and/or they focus on the negative.
I am 47 a female. I am not bitter like those women and I know what you are talking about.
I think a lot of those women who are bitter are too in their heads and they don't fill their heads with more positive thoughts.
For me spirituality prevents bitterness. Focusing on what you do have and the beauty in your life vs focusing on what is wrong.
I have repetitive issues in my life as well and I think there is a lesson in there. For me I think others were mirroring the way I was treating myself. They were a mirror of my inner dialogue. Do you think that could be happening with you?
. I would have felt so sick at the whole having to speak to him. 
