40 years of grudgeful
This is crazy but I've held onto a grudge against my mother for 40 years. In adulthood it's transformed into drastically overeacting whenever my partner does something which displeases me or annoys me. I can feel the grudge physically in my chest and stomach as it spirals out of control and pushes me towards an almost insatiable desire to feel the hurt and diappointment of whatever banal episode has led to my resentment.
The grudge that I develop is so strong it can last for weeks - I cannot seem to let go and yet my mother has passed and these immense grudgeful feelings continue to sabotage my relationship.