Depression and Relationship problems

Since I’ve gotten pregnant my depression has hit an all time low. My boyfriend seems to be drifting off and doing his own thing from now on and he doesn’t seem to listen. All I ask for is communication and we used to be so good at it but now he doesn’t answer my texts for hours, barely acknowledges how I’m feeling and I just don’t know what to do anymore. It’s tearing me apart and sometimes I just sit there crying and wondering what I did wrong for him to act this way. What do I do?