Single mom starting today

Going to raise my son by my self. I'm 31 weeks and the sperm donor ( my now ex) don't want anything to do with my unborn son. We was fine until today when he got caught cheating. He blamed me for being nosey. He was sending nude pictures to another woman who is married btw. I confronted him and now he's done. But he's still living in my apartment with me. It hurts so much knowing he never cared or loved us. My son shouldn't be blamed for this but yet he is. My heart is broken for him and myself. Can't believe after everything he would do us like this.