So im trying to understand wtf is going on, does she not feed her child, so he ate the dog...

It's confusing me too

I think her child that she sees is actually a dog. And she sees the children she abducts as dogs-- explains the chapter where the dog she adopted died, it's bc she fed it with dog food. It's the same child that was found on the balcony in a box later on. Her real child died years ago. Then she adopts a dog to cope up (but she thinks its her child) then she abducts children (she sees them as dogs) so her "child" wont get lonely. Hope it helps bc i know i suck at explaining