I'm at art school now, and I'm finding myself swamped with assigned artwork, and I'm somewhat struggling to find time for my own. But I do feel that I can still make time for comics, but I have to be careful of my schedule. Because my current schedule is unpredictable, lately I've been sticking with one-shots, such as Fish. I try plan my comic making time during breaks, so it lessens the amount of stress during exam weeks, but honesty, I'd rather be making comics all year around!!!!
Motivation is hard, and I had days where I fought against the lack of it. From what I learned is that if you're lying in bed, staring at the ceiling... and feeling sick about your comic, it is probably wise to get some rest first. I don't know about your habits but for me I burn out if I try too hard, and I will not be productive until I recharge. But other than that, what motivates me is the story. Personally I like the journey more than the destination, but if the journey has no end it becomes very non-motivating... In other words, it's good to have an ending (or any destination), because it will give you a goal.