Curbing bad habits?

My relationship with my parents and entire family really has always been stressful and on the verge of abusive both emotionally and physically. My SO says that it is abuse but I always kind of thought their actions were usually my fault. I tend to pick fights and I always speak my mind. Obviously I drove my family crazy. Now that I've moved out and into my SO's family home, I find myself picking fights with him. I usually recognize it and apologize but it's starting to happen more and more often. I love him with all of my heart and I know that I want to marry him. He never abuses me in any way, he knows when to walk away and let me cool off, and he treats me like a princess. It's almost as if I'm trying to sabotage our relationship but I don't want to. I feel like I enjoy or like the strife. 😢😢😢 I want to change because he deserves better. Hes never treated me badly and I am continuously fighting over stupid stuff and "hitting below the belt" metaphorically in fights. I feel like I can't fix it. The other day he asked if I felt stuck just bc we live together, have the wedding planned out and paid for, and we share an account. He just wants me to be hapoy, but he doesn't understand that I AM already happy and so in love with him!