If you see a little child you can see the spark in their eyes. As we grow we keep loosing that spark. Life gets harder and keeps sucking the motivation out of us. I think motivation is the most precious thing in life and we loose it so easily without even being fully aware of it. As I grew up the most difficult thing I've faced is to keep myself motivated. The dreams we dream don't just come true. Our reality is totally different from our dreams.
I guess it's normal that we come to a point where we lose motivation. What you can do is refocus yourself to your goal, a SMART goal and then you'll be able to get past it. Find your drive and think of the things would inspire you to keep going. May it be your family, your special someone, a friend, or yourself. Remember that everything that you do has an impact to your personal life. Keep in mind that that you should never stop dreaming.