Since summer is only about a week long here in Wisconsin, I purchased a "smart trainer" many years ago and ride on Zwift for at least half the year. No, it's not as good as riding outside, but I find that the group rides, races, etc., are "entertaining enough" to keep me riding during the off season. I'll also listen to podcasts when I'm riding indoors to keep my brain entertained. Since purchasing my smart trainer, I find that my fitness level stays constant all year long as opposed to getting totally out of shape over the winter and then spending the bulk of summer just trying to get fit again.