Help for disrupted adoption?

MrsB2Be2008

I posted a couple of weeks ago that we brought home a newborn baby girl in hopes of adopting her. Well, we've had her for 2 .5 weeks and found out her birthfather won't sign. To prevent him from getting custody, the birthmother is going to parent, even though she really wants us to adopt the baby. We are devastated, and don't know yet when we will be returning her to her birthmother. Has anyone experienced disruption? Advice for getting through?