Total shock, lost my motivation


I have been meaning to start the 8 week fb workout for months now. Today was the first time I realized that I can't put it off anymore... I kept scheduling it, then postponing - I have mid terms, homework, etc. But I got home from work today and realized I don't fit into the jeans I did 6 months ago. That was a shock to me. Up until now I've gone through phases where they've been comfortable, or tight, but they have never NOT fit.... I feel like I'm starting completely over again, and I'm just overwhelmed, and frustrated. Especially because I had no idea I'd put on this much weight. I'm afraid I'm going to start this program and run out of steam halfway through. Does anyone have any tips for staying motivated with a busy schedule? I work 32 hours a week, and go to college full time.