He said he is not happy

Today my husband told me he is not happy and that “i wont let him leave” responding to my complaining about some inappropriate comments he left on a girls page on instagram that he still has communication with. He said why cant i change and be a better wife then he wont have to make those comments. He has told me many times before he is not happy and he is miserable or hasnt been happy for years but usually he takes it back and says he didnt mean it. What he said tonight really sunk into my soul because i am pregnant and im sleeping next to him with our 2 yr old and he says i am not letting him leave, i told him he can go if he isnt happy and he said i should have thought about that before i became pregnant. I have tried so many things to make this man happy, or fix myself with the issues he complains about but still he continues to complain and say i need to fix more. I know its not me and the love is gone and i need to move on with my little girl and soon to be baby. Ive tried to leave before but he pulls me back and says he loves me and the baby and wants us to come home but when i do he is still miserable. I am really praying i have the courage to leave. This marriage has sucked the life out of me. I dont even recognize myself anymore. I have nothing left to give.