I am so sorry this happened to you. This may be the best thing that could have happened however. He was in prison, not good, may be sent out of the country, not good, ambivalent in his feelings for you, very cut and dry attitude. I've been thru a few serious relationships, and there is nothing worse than realizing that your spouse or significant other is very half-hearted about you. Later you will see that they were very insincere from the start, you were head over heels in love. The good news is, you will find someone better. Don't rush.
If he's not a financial or emotional help, tell him to move out, and give back the key. He might think this set up is just peachy. Its not. Get rid of him. He let you down big time.
Enjoy this time that you are pregnant. Get some photos of your big belly , smiling and laughing. I love showing my kids what it was like for me when I was pregnant. I want them to know that they were wanted. I know its uncomfortable, but I would give my right arm to feel my baby (ies) moving inside me, to hold that tiny little bundle close, smell that new baby smell. Surround yourself with friends and happy people. Enough crying. Keep posting. We care about you.