Your doing great, get the negative thoughts about FIL out of your head, maybe he is serious that after everything that has gone down, that she needs you and his granddaughter needs both of you.
You did great, and are doing great. Cannot wait until you get to tell her that D3 loves the new playset.
You are now starting to have some control over the situation and it should make you feel a little bit better about everything. Just keep it up, when she calls next time, how 'bout saying that you and D have a playdate somewhere? What can you do for you and your daughter in the next couple of days.