H.F.
I'm not sure which part of PA you are in. I live in the Pittsburgh Area. The Women's Shelter offers free legal service. Also, you can get a free attorney through legal aid.
My friend had been having problems regarding custody of her daughters and leaving the state. Perhaps you can talk to your ex about working out a custody agreement that works for both of you. If you have an agreement worked out in writing and approved/notarized through the courts perhaps your ex will be more understanding of your needing to move. He may insist that you agree to abide by custody arrangements/agreements/disputes being settled in Pennsylvania.
In the meantime, please check into free legal aid in your area. I do know that if you leave the state with your daughter, your ex can have the courts force you to come back. There is a special form you can file to get permission from the courts to leave the state but that can take months as well.
I wish I had better news for you. Your best bet is to seek out free legal aid. Good luck with your custody issues and with your impending marriage.