OK, well, this was me 13 years ago and I would say 100% stop breastfeeding if it is making you feel this way. I didn't stop and it was by far and away the biggest mistake I've made as a mum.
When I was pregnant, I so badly wanted to breastfeed - for the health benefits, the bonding and, frankly, the convenience. The reality was that my DD didn't latch properly, took hours to feed and really was never sated. I struggled for weeks, seeing several, mostly unhelpful, health professionals.
I eventually ended up combination feeding for months and months, which was the worst of all worlds as I was pumping, BFing for hours plus bottle feeding, sterilising and all the rest of it. It was stressful, tiring and I felt so guilty and resentful. It really robbed me of precious bonding time with my DD and if I had my time again I would never pursue it for so long.
Of course, hindsight is a wonderful thing and I know how you feel and how difficult it is to call it a day. I encountered one or two lovely midwives who tried to convince me that it would be fine to switch to formula. I couldn't be persuaded but, honestly, they were right, it wasn't worth it. Don't feel guilty, just enjoy your time with your beautiful baby.
Also, re health benefits. A lovely friend of mine has 3 kids:
DC 1 - had same probs with BF. All a bit stressful, baby failed to gain enough weight, ended up combination feeding, etc etc
DC 2 - entirely FF from 2 wks old
DC 3 - entirely BF. All went perfectly, fed beautifully, gained weight, friend determined to crack it with this one.
They are all strapping teens now but, healthwise, it was DC 3 who had the most health issues - nothing really serious but lots of allergies, asthma, mild aspergers. DC 2 has turned out to be the most healthy and robust. It's probably genetics and nothing to do with feeding but I think it's an interesting outcome.
It really will be fine to stop. Good luck!