He was cheating on me I was pregnant with his 1st boy and while I was and the hospital having him he was having sex with his first baby's mother come to find out she became 1mth pregnant she moved to California then when she was due he left me and my son to be with her and his two daughters now he's telling me he's not with her but she's telling me they are

Because you are allowing him to, if you kick him to the curb, get a child support order on him from the court, and if he wants to visit his child, he gets a child visitation order. He visits the child, not you.

It is because by the way you write, you have bought into the baby daddy myth and let him come and go like a revolving door