I think it sounds like you are very committed to nursing. Since he is only resisting to nurse once a feeding every few days, it does not sound like a strike, nor does it sound consistent enough to be about the bottle.
I can see how this new behavior has you feeling confused. Both of my children around this age would want to nurse, and then hear or see something and stop nursing as if they never wanted to nurse in the first place. I found that their cues that tell us that they want to nurse changed as they got older. The thing that helped the most was removing them to a quiet room away from activity, noises, and toys and just relaxing with them for a few minutes. They were much more likely to focus on nursing in a quiet environment than if I just nursed him wherever we were.
I also found that once they were more interactive with their surrounding and more active that they could go for much longer without nursing when they were awake. Another thing that tended to happen as they approached a year and older, was that they wanted to nurse to be comforted and not just because they were hungry. I interweaved periods of reading stories and playing with him to give him my attention in addition to nursing.
I say just keep up what you are doing, but only give him a bottle when you are away at work if that is what has been working for you. Both of my children nursed until they were 2+, and you can feel free to email me with any questions.
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