Jasper, sorry to hear that you've had a difficult few weeks. I just thought I'd add my experience here, although I may preview it and decide against it, since my point of view may not be to everyone's liking (but we're tolerant here, are we not?) Here goes:
I really wanted to breastfeed. I buy organic food, am anti GM, and wanted to be an earth mother and "good" mother. I knew it was the best thing to do.
However, it just didn't work for me. My ds wasn't putting on weight, I was beside myself with panic about it, I didn't like it, was in pain and my dh couldn't help me with night feeds or with feeding at other times.
So I gave up, mainly because I'd promised myself that I would do my best and give it my best shot and I felt that I had, but I'd also promised myself that I would not beat myself up about it if it didn't work (for whatever reason).
So, when ds was 4 days old (sorry, but that was my limit and I know you might all think I'm pathetic, but that's what happened - we all have our different tolerance levels) I went to bottles. I did cry and I did feel I'd failed.
But ds was (and is, 4 years later!) fine, happy and thriving, my dh was supportive and able to give me a break to sleep sometimes and I just accepted it and moved on.
I know "breast is best" - to quote an ad slogan at you, but I also think that women are made to feel terribly guilty about using formula and that those of us that can't do it deserve a break and to be credited with making the decision that is best for us.
I had to contend with the girl behind the cheese counter at Sainsbury's asking me, when ds was 5 days old "is he breastfed?" and when I replied in the negative, she said "well you should, they're more intelligent, breastfed babies" ("and you're working behind the cheese counter, love" is what I should have said but didn't
Anyway, I suppose my point is that you can give yourself permission to stop if it's not working and that's what happened in my case. I got over the guilt and am happy with that. Good luck, whatever you do. HTH.