At the end of my rope

I really need help/advise. My baby is 5 weeks old today and we breastfeed with a nipple shield because my nipples are soft and are difficult for her to latch on to properly. She has done it a few times with out the shield, but never stayed on longer than a few min. My pp recovery has been difficult. Had a repeat c section with no complications and that was fine, but got mastitis a week later that turned into a mass on my right breast that had to be aspirated. Thought things were getting better after 3 rounds of different antibiotics, but got a fever and had pain in my c section area so went to the ER. I got antibiotics and a ton of different tests done to rule a bunch of stuff out. The Dr is thinking it's still my mastitis and I'm on antibiotics again to hopefully kill this off. Now what I'm getting at is my baby will not have a full feed at my breast. She can be so hungry, and start feeding, but then stops after a few min and just soothes on me. That can be ok, except she freaks out after I take her off because she realizes she hungry. And this cycle continues. She will only have a full feed from a bottle (breastmilk). I'm sitting here crying, feeling defeated after going through so much mentally and physically, and now she won't breastfeed. I don't know what to do.