How to Stop Talking About Trauma with Your Partner

How do you stop talking about your trauma around your partner? I was in an emotionally and sexually abusive relationship about 8 years ago when I was a teenager and it lasted almost a year and thankfully I was able to get out of it, but at the time, I didn't realize what happened to me was abuse since I was invalidated and gaslighted for a while, so I went through years of no signs of ptsd or trauma, but once I reached college, my trauma started flooding me I assume because I didn't take time to process it as a teen, and so my partner is confused why it's affecting me now and my family thinks it's odd since I seemed "normal" for a good few years. I'm not sure why it's affecting me really either, but it's affecting my relationship as well and stresses him out when I mention the guy who abused me or the memories, and I don't mean to mention it, that's just how I cope. Any advice or thoughts would really be appreciated!! 💜