DDG is a damn clown so automatically, he's at fault, regardless of what it is.
That said, honestly that is not an overreaction on her part. That was actually quite reasonable and measured response. I'd give her more credit if she wasn't parading the baby around herself but she has a point nonetheless. Also having a dude who has shown a level of irresponsibility in the past around her baby is enough to be mad too.
Again, DDG is a whole ass fool. fukk that guy.