If you're a human and feels demotivated sometimes, that's natural. Don't take it too seriously. But, if you’re feeling demotivated all the time, you need to get out of it immediately.
Sometimes, we get stuck into the problems from where we don't find a way or one can say start losing focus on things we shouldn't have to. Irrespective of all these factors, we shall keep on trying to get back on track.
Our goals can be deviated. But, our dreams don't die. The more, we deviate from our goals, the more we bury our dreams.
I myself can't stay motivated all the time. But, whenever I feel down, I keep on trying to keep my morale high, stay calm wherever I can and keep moving with the flow. And, if in case, this feeling doesn't get stop, I start trying ways which brings back my positive attitude and happy mindset.