Try and bottom out what’s causing the peedoffness. And be honest. There must be a reason (or two).
As previous poster’s have referred to, regular exercise is something I ‘need’ otherwise I get restless, then fed up, then unmotivated and then unimportant things start annoying me and I get impatient with stuff.
At this time of year when time out on the bike is minimal I usually do regular weights routines, maybe a bit of running.
I have learnt that a routine of sorts is necessary for me.
EDIT: also, personally I find using winter as a change from biking is a good idea.. I cycle most days for most of the year what with commuting, and I definitely benefit from a couple of months of doing something non-bike related.