I am having a child with my ex and she left me for her ex-girlfriend and won't let me be part of the pregnancy... but I want to be there for it all... but the main thing is I want my child to have my last name... do I have any rights... or will it have to wait for me to take her to court?
Please help

I'm afraid not. The mother has sole rights to naming the child regardless of paternity. Taking her to court won't help either. They won't change the child's name without her approval.

You WILL be able to go and get visitation/joint custody if you choose. She will also get child support.

Sorry, you have no rights till the child is born, Once the child is born, you file for paternity, using a DNA test, and ask for court ordred visitation.