Breastfeeding help

So I really want to breastfeed. All the nurses helped me at latching him on, yes I can feel the difference between him just being on my nipple and a full open mouth latch. All the nurses said he was on their great but it felt like a nail file on my nipple. I sucked it up but now I can’t even let him near them because they hurt SO bad I just cry and now they are so cracked and damaged. I can’t stop crying because I feel so bad because I really wanted to breastfeed for all the benefits. I’ve been supplementing with formula and trying to pump as much colostrum and add it in there so he gets some. Anyone have any advice on either the breastfeeding part or the guilt I feel.