I have found that cheaper strings I buy in ten packs tend to last longer for me. If I decide to "treat" my guitar to a nice set of boutique strings, I can be sure I will break one within a few days. Usually the B or G. I tend to fool myself into believing that differences in strings will help me sound better. Not at my level. Another few hours of practice....now that will make me sound better! Oh, but those fresh strings do feel so nice under the fingers. Anyway, back to the problem at hand, if you are breaking consistently at one tuner you might try moving them around. Swap out the G and High E heads and see if that helps. Maybe you have a tiny burr in there that is cutting into the string.