I also find it hard to ride this time of year. The days are short and my time is stretched between work, children, home, church, and other commitments.
My solution. I now get up at 4:30 am and am typically on my bike by 4:45. Yes it is dark, get lights. Yes it is early, go to bed by 9:30. I am able to get in about 20 miles and be back by 6:00. Some mornings, it is very hard to drag myself out of bed. However, I ALWAYS fell better after sweating out some miles and not having to stress over when I will find the time to ride later in the day.
Quit making excuses why you can't, make it a priority and you will find the time.
Good luck!