I don't believe in "finding motivation." When people ask, "how do I get motivated?" I never know quite how to answer because honestly, I don't really believe in motivation. At the end of the day you just have to get up off your butt and move. Or resolve to stop (for things like smoking) and then (this is the key) follow through on it. It does not matter why you do it, at some point you just have to do it and stop with the excuses.
There are certainly hurdles: not enough time, physical limitations, you've had a bad day, it's the holidays, etc. But it doesn't really matter if you have all of those excuses or none of those excuses. The world doesn't say "oh, okay, well I understand that you have three kids you're chasing around so I'll ignore that bag of gummy worms you just ate" or "I understand that you're in a lot of pain and on drugs that slow your metabolism, so I'm going to make sure you don't lose your fitness gains even if you lay in bed for the next month." Wouldn't it be nice if that was the way it worked? There would definitely be more justice in it. But it doesn't happen like that.
Is it fair? Probably not. It doesn't matter. It is just the way it is. Christmas calories still count. They count for the 23-year-old woman with a high metabolism and no children and they count for the 43-year-old woman with a thyroid problem and 4 kids. They may count differently, but just because we think that cosmically, it should all balance out and "be fair," it doesn't mean that's reality.
So I think that when people say they can't find motivation or they're just not motivated, what they really mean is that they haven't accepted their world as it is. Once you accept your limitations and hurdles (kids, chronic pain, the holidays, whatever), then you can look for ways beyond them. My way of getting past my hurdles is most likely different than yours. There is no one-size fits-all answer.
But at the end of the day, if you want to see results, regardless of the reasons, regardless of the excuses, regardless of your limitations, you really just need to get off your derriere and take action.
My dog Max, who has more cosmic justice than he knows what to with: