Staying motivated to work out

Ashley • 22, Night shift nurse, Native American. Modified, sassy, sarcastic Sagittarius. Suffering from PCOS. I love cats!
I always struggle with having a regular gym schedule. I'll do really well for a month or two and then I just quit. I pay for a gym membership and that doesn't seem to keep my motivated. I have PCOS so keeping my weight down is both extremely important and very difficult. When I eat right and work out regularly I notice that I feel/look better even if the weight loss is slow. But I can't seem to keep it going all the time. What do you guys do when the last thing you want to do is go to the gym?