For my training, I have a similar schedule as you do - I do long rides on the weekends, and then spin early in the morning twice a week. Sometimes I go through a week or so where it is VERY difficult for me to get up at 5 to go spin or ride early. Often this is after a very hard training weekend.
I know it is so hard to get up so early, but try getting to bed a little sooner, and just reminding yourself as the alarm goes off how much better you will feel if you do go ride. Once you get into a rhythm of getting up early for your ride, it does get easier. Remind yourself of that, too.