What possible actions can I take to protect myself and my child's future?

My wife moved to Oregon to meet a man she met on the internet nearly six months ago. She did not say if or when she would be coming back. Her parents live with us and she said she asked her mother to watch them in her absence.Her mother does help with some of the cooking and being there for my daughter when she gets off of the school bus. But I have been the one taking care of all of her financial needs,medical and schooling with no help in those areas. It has been brought to my attention that my wife intends to return home after the holidays with this person she met and that she wants to have joint custody of my daughter. I feel that if I do not take some sort of action then both my wife and possibly her parents will try and dictate my daughter's future. I don't even know if I can afford to hire a lawyer or what my parental rights are in this situation and I was hoping to get some guidance and possible options.