How Do I Leave?

I'm a 35 year old guy currently in a 3 relationship with a 42 year old guy. From the start, our relationship has been rocky with arguments, personality conflicts,etc. Over 3 years, we've found love,compion & concern for one another, but no at all. He brokeup with me twice but asked me to come back, during which I felt that we should have remained apart. We recently relocated to another part of the country, amidst our relationship history and drama. We get along okay but periodically personality conflicts creeps up on us. I feel as if I coast along waiting for the next big argument, which will happen. I am tired of the arguments(he has a horrible and negative attitude and personality). He gets extremely angry from the most minor things. If I joke with him, ie, call him girl, *****(in a playful, joking way). I've felt extremely unhappy for months. Last week, we closed on a house, which I felt was a huge, stupid mistake on my part. I feel trapped & that we should end, but how?