Single monther

Im now 8 weeks pregnant and my now ex bf doesn’t want the baby. He did at first till his ex accused me of cheating on him. The guy is from my passed and about 4 months ago we broke up for two weeks.the guy was only going to say hi for my birthday but nothing ever happened. His ex is assuming I cheated and he’s siding with her. I have no idea why he won’t believe me there’s no proof nothing. He’s now pressuring for abortion and I refuse !! Not because of his ex. I didn’t see my self alone and becoming a single mother for a second time I’m so sad any advice?