Breastfeeding gone wrong please help

Now I understand breast milk is the best milk for newborns. I’m experiencing difficulties where she’s latching on fine but she’s tearing my nipples apart. I have open cuts on my boobs an every time she’s latching on she’s pulling on the cuts and making them worse. I’m using nipple cream an I’m still trying to pump but it’s not helping so much.. I feel so guilty if I decide to switch to formula milk ( Similac ) idk what to do.. I don’t think she’s getting enough breast milk from me anyways because I tested to see if she’d like the formula an she drinks it in MINUTES like she’s been starving.. I’m so sad I failed..