Getting better as an endurance athlete is all about putting on layers of structured training and 'educational' competitions from season to season.
Patience is key and you should expect ups and downs along the way, but if you learn and keep striving you will grow!
For many athlethes another long and demanding season is coming to an end, and signs of physical and mental staleness is starting to show up!
The many hours of focused training and demanding races has taken it's toll on the body, so it's time to step back for a while to recharge before base training kicks in. In other words time for off-season!
Off-season doesn't mean you can't or shouldn't train. You are more than welcome to train, but you just need to rewind and go easier and with a different purpose than normal. The overall outcome of the off-season should be that you recover and freshen up, thus getting ready to put on at new layer!
So training during the off-season should be fun and based on your desire to train! Do you feel like riding your bike, go ride your bike, but do it with a more recreational purpose instead of a training purpose! In other words, don't go too hard or too long, but enjoy along the way and finish with a feeling of wanting more. In that way you will build motivation instead of draining your motivation!
Off-season is also perfect for dedicating time to some aspects of training, that you normally don't prioritize or don't have the time to fill into a tight schedule.
So maybe try to get started on strength training, if that's been missing on your training schedule the last season, go for a run instead of just riding your bike (but run easy as running are hard on a cyclists body) or try to do some yoga or work on your mobility.
In that way you will get some adversity from all the time spent cycling, and you will work on important physical aspect, that will help to make your body more durable and healthy. Which in turn can be very helpfull when you start the hard training towards next season!