My old roadie went years---yes-- years without a flat and would still hold air this year before I completely replaced the tires and tubes---although I didn't ride it this year until the replacement.

I've generally found when I start having flats its time for a fresh start with new tubes and tires---and a new rim ring here and there. The new tires-- etc will last several years---then replace the whole thing again-----Also keep your eyes on the road(literally) and don't forget that patch kit---lol.