Could you date/have sex with a dad to be?

Okay so I’ve been seeing this guy for a year but I’ve known him for about 3 years but to cut it short he recently found out she was pregnant and like a month after that found out it was a girl. My feeling were so hurt because we talked about dating etc so I ended up blocking him on literally everything and somehow he still managed to get in contact with me🤦🏽‍♀️ he tells him how much he wants to be with me and begged to come over my house but I don’t think I can do it I’ve been telling him NO for a month but he still tries to talk to me 😭 Could you have sex with someone who has a baby on the way? Explain how you’d feel