Why is my husband staying with me?

My husband doesn't like me much. It's clear to me. I realize now, that he married me only because he wanted children and he felt he didn't have much time due to his age, but after 4 years of marriage it was determined that I was infertile. He used to tell me I was sweet and kind hearted and seemed to love me so much it was incredible, but for the last 6 months he's been cold, uncommunicative and impatient with me. He gives me perfunctory kisses when he has to and every few days wants to have quick but there is no love or pion in his eyes anymore. I have brought up how I feel on numerous occasions and have asked him if he's happy and he says he's not but never blames me, always blames his job etc, but he's still very cold and impatient with ME. I think I'm an intuitive person and believe that he is very unhappy with me, and thinks he made a bad choice in marrying me. I ask him about it and he says he doesn't want a divorce, but he seems so unhappy. Is there another reason why he would want to stay? We don't seem to have anything in common and we never laugh together. I would like to cuddle more and be happy again but I don't feel like I am welcome to. It feels like he has a wall of ice between us.