in "the miller's daughter" when emma held regina with a sharp object to her neck, why wasnt regina mad at cora when she chose the dagger over her?

My impression is that had that not happened Gina would never have done what snow suggested. So it did effect her feelings. She didnt just let it slide.

my guess why Cora didn't chose Regina over the dagger is because she didn't have her corazón yet so she had no real feelings and just wanted power..once she had her corazón tu can see the amor she had for her daughter right before she died..

To be honest I don't really know. But minavradawn's answer seemed legit.