And I'll say it again: Exercise is such an easy habit to break. You must use CONSTANT VIGILENCE (as Professor Moody puts it), lest you allow your muscles and good health to suffer. That's where friends and variation come in. It is much more difficult to sluff off when you have friends who are waiting for you or are out suffering while you bask on your couch in front of a fire.
Since my excellent performance in Gruene Nov 5, I've been on the bike a total of five times. Yesterday's 32 mile cruise was less than stellar and showed me how quickly the body loses training. I can't blame my friends. The holiday season is disruptive and only the most dedicated stick to a rigid schedule. It isn't that I've gone couch potato. My trips to Gold's have increased and I'm doing core training and stretching more. This variation will help in the long run.
If you haven't already, find a group/club you can exercise with. Let the peer pressure be a positive inducement. I only need a few rides per week in the next couple weeks to get me through December. January and February are generally clear and are great months to put in some serious training.