Why do I keep breaking guitar strings?

I have played guitar for 17 years without ever breaking a string. In the past four weeks, I have broken four. The first time I thought it was simply because I was long overdue for a string change (which I usually keep up with)... but they keep breaking. Usually it’s the G string, but not every time. Once it was the D.

Keep in mind that all but the first time, these were brand new strings. They’re not rusted or anything. I thought it might a sharp spot on the bridge, but I’m starting to doubt that given that the I’ve had two Gs break at the bridge, one G break at the nut, and one D break at the bridge.

One of the times I was playing pretty hard. Two of the times it was what I would call medium strumming. This last one broke while I was lightly finger-picking while sitting on the couch.

All of this has happened with the same guitar. It’s a Taylor acoustic with a cutaway dreadnought body type. I am using Elixir Nanoweb .013s, as per Taylor’s recommendation (they build the guitars with these strings in mind).