My ex boyfriend has custody of our son and I was order to pay child support and I get visitation but every time I went to get my son he wouldn't let me have him because his new girlfriend didn't think it was a good ideal. Then they got married and I tried again to visit my son and he had a restraining order put against me and then told me that he was going to get me for abandament of my child when he wouldn't let me see him so that his wife can adopt him can this happen?

Get to court and get an order of visitation. If you already have one, get it enforced. A child has a right to two parents, and he does not have the right to stop you seeing your son unless a court has ruled you completely unfit.

If you are paying regular child support, your ex will have a very hard time proving abandament.

You have a right to see your son, and more important, your son has the right to see you. The fact that your ex is trying to prevent this is a huge black mark against him, which family courts will notice.