i have a secret blog

I used to be in an emotionally and mentally abusive relationship. so after we broke up I started writing to help get all the feeling and emotions out of my system. my BF and I have been together for about a year and a half now, and I'm thinking about showing him. in worried that he might get mad or upset about it though. I confessed some stuff in my writing that I know he's not gonna like to read. my BF and I had a lot of problems with my abusive ex when we started dating and a lot of what I wrote is about my ex at the beginning, but now it's all my BF. I don't want to bring up old stuff that caused problems between us but I don't want to keep this a secret anymore. I'm so scared about him finding that I want to show him because I'd rather him know because I showed him than him accidentally find it in his own. should I show him and hope that he will understand... or just continue to keep it a secret?

p.s. this is the first time I've mentioned this particular set of writings to ANYONE. Not even my friends or family know about this