I don't know what it is exactly, but with creative ventures, there are a lot of things that come along and try to deflate whatever it is I'm doing. Maybe you don't have this problem, but I know that I do. It could be some comment online, a piece of advice, a bit of confusion about why someone else's venture seems to be working, etc.
Whatever the case, there's always something that seems to put a dent in the spiritual momentum of the creativity.
So what can be done? The obvious answer that people from afar like to say is "don't give up". That's easy advice, and not necessarily bad, but just plowing into a problem without the right mindset can cause resentment and things may start to go sour.
My dad used to ask me, "Well,...what *can* you do?" My mom's version of that was, "So what do you *want* to do?" These are both very good questions. But they aren't questions to ponder, they are questions to act upon in order to keep the momentum flowing. Because the most damaging thing to me as a creative is the lack of momentum in ANY direction.
Draw a picture.
Try new music.
Go to a museum.
Make a dumb Facebook post.
Reply to a thread.
Help a friend.
Try a new angle.
ANYTHING that helps me let go of the resistance and get my mind back into creative mode.
Whatever the problem, I can't let myself lose the drive to keep moving. I have to get re-aligned and I have to keep going. That's just the person I want to be. Because once the flame goes out...poof.
The flame must be kept alive.