Why is marriage so hard?

F 37 M 38 married 3 years in September together since 2018. We can't seem to get along. He doesn't seem happy. Our house is a disaster we never do anything fun. Everything I do doesn't seem like enough. We are trying to have a baby and now I just feel like it's a mistake. I feel like I should just go back on birth control and forget about it. I was single for a long time, I was so happy when we got together but now I'm just so tired of fighting and feeling like I mean nothing. I am not a good housekeeper. I try to be the best wife I can. I'm trying to declutter and organize but mentally I'm exhausted. Work has just slowed down these past few weeks. I had been working anywhere from 50-70 hours a week. I will admit i don't care about myself anymore and i don't know how to change that. My husband isn't being supportive of any of the efforts ive made to better myself. I'm crying in the bedroom while he is laughing at the tv in the living room. I'm just so tired of everything. i wish i could be the person he wants me to be.