My son wants me to break up with my so

My so and I have been together for a year now and my 7 year old(from my previous relationship.sharing joint custody)wants me to break up with him. He blames him for the reason his father and I are no longer together(he's not completely wrong) I feel like a horrible mother for saying this but I don't want to. This man is literally the love of my life next to my child of course. He and my so have only spent a couple times together bc he travels for work(long distance relationship) but the Times they were together it was disastrous. Its like I have these two amazing pieces that make up my heart but they don't fit together. My son says he wants nothing to do with me if my so is still in the picture.Anyone ever been in a situation similar to mine? What did you do?