Get out now, why wait? He's not the White Knight on a beautiful white horse.
Do what's best for you and your baby.
An unmarried male has no rights to a child he alleges to have sired, unless and until he goes to court and attempts to enforce his paternal rights.
The unwed mama, on the other hand, has all of her maternal rights by virtue of carrying the child to term and birthing it.
Stop worrying about what the cheater will do, and do what's best for you and baby. Your family loves you, you love them. You should have no stressers and be around those who love you. After the baby arrives, everything and everyone is doing well, then you can worry about the cheater.
Its easier when a woman is pregnant if she has a strong support system. You have one, go to them.