I was just in a slump for months, it was horrible. The main reason was that I had a round robin here to finish and I had no inspiration on what to do with it. I usually, but not always, work on one quilt until at least the top is done because it made me feel bad to have UFOs. Well, since I wasn't working on the RR quilt I felt I couldn't work on anything.
I had to make myself start working on the RR quilt and there were days when I literally sewed 4 pieces and got up and left the sewing room. I just kept making myself work on it a little at a time and then suddenly I had my enthusiasm back and finished it in short order.
Since then I've worked on my other things almost every day and even started a new quilt since I'm at the next stage of the first one AND I am working on quilting another one.
It just takes as much time as it takes. Maybe you need something new to inspire you, a small project like a table runner.