Hi I am sorry you all are in such a complicated situation. It must be difficult for all involved. It sounds like Eric needs you all in his life and you all have built a relationship with him. I think he must be heartbroken about losing all of you not just your daughter which is probably why it is so hard on him.
I think it can all work out even if it takes a little time for everyone to adjust to the new circumstances. Communicate clearly what you expect and how you all feel so that all expectations are on the table. Keep courage and faith, I'll be praying for you all.