For me, writing reopened a lot of old wounds and also brought back memories that had been suppressed. However, it also brought me to a point of being able to finally let go and move on. I never thought I'd be able to let go of the resentment, but I feel more at peace with that past than I'd ever have imagined. It's shaped who I am, after all, and if I continue holding that resentment, then I hold it against myself too.
RE: What to Do When Your Writing Reopens Wounds