Exercising Question

Vanessa
Ugh! I'm 30+4 weeks and for the past week my energy level has decreased, big time! Between pregnancy, chasing 2 Little's and my teens being on Christmas break and being, well teens lol, it's super hard to get the energy to do my workouts. I've been doing so well working out this pregnancy and I'm getting upset that I can't even force myself to exercise like I can on just lazy days. 
For those of you guys who exercise frequently in pregnancy what do you do to get yourself motivated?