If you lose the motivation to create, its usually because of the nature of your genre, or your workflow is irregular.
Let me explain.
I used to draw a satire comic about a cat and dog, poking fun at society and its norms in general. But satire takes a certain state of mind to get the creativity going, and its not easy to use a leering eye to look at society all the time. You have to use a very condescending attitude in order to grind something out. So I only reached 21 episodes before I gave it up. Updates were irregular, and I disliked working on it. (You can take a look here.)
Then I did a romance comedy called Salt n Pepper (defunct. It got shut down because I started a company around it with a partner.) Romance was fairly easily to get inspiration for because its basically playing in your face in every dating ground you see. But a schedule of monday, wednesday & friday was taxing on me, and i gradually disliked working on it too because it was so taxing. Eventually I have to give it up because I had to work on websites in the day.
So fast-forward to the present where I am now drawing Thirteen Maidens. Even before I began on this comic, I was reading up and studying horoscopes for a year. I sketched and designed and planned all my characters before deciding to launch, even before I began. This is very counter-intuitive and completely against the best advice given on the forum, but I wanted to make sure I won't write myself into a wall.
So if you feel that you are losing motivation, I would say that its your workflow that is killing your mood. I do a Monday/Thursday release because its not as taxing, though the results will be slower. I picked a chibi style because it gives some leeway on the polish, plus cute goes well with gag comics. I picked horoscope as my schtick because I feel this topic will never drive you into a dead end. People have been talking about horoscopes for 2000 years and still have things to talk about after all.
I hope my story gives you some insight towards picking up your motivation. Remember, its a marathon, not a sprint. You will want your first 100 comics out before something good will happen. Be sure to plan for a long long journey. First revise your workflow, and make sure you like the flow, regardless of whatever people tell you. (Colouring is very soothing, i tell you.)