Tell her your door is open and she can always come visit her granddaughter, but I wouldn't be emailing pictures of your daughter to her. That just validates her bad behavior. She thinks she can cut you off without repercussions with her granddaughter. Nope, one of the repercussions of cutting you off is losing her access point for her grandchild.
This is abuse. Abusers project their bad behavior onto others. You know, "Well, YOU left Jehovah." Nope, nope, and nope. She can't have her cake and eat it too. This is her choice and she will need to live with the consequences. There is no way I would email her pictures of your daughter.