I went to the International Center of Photography for awhile, and one of the classes I had was called Roll a Day. The concept was as simple as it sounds -- you have to shoot 36 exposures a day, no matter what. Each day of the week you have to print a contact sheet and one 5x7. You have to print the blank frames if you did not finish a roll (or 36 digital shots). Each week you pick one image to make an 8x10, every two weeks an 11x14 and every month a 16x20. Tack the work up onto the wall and live with it. You need to confront it if you want to learn and break free of the stagnation.
Forcing yourself to just go out and take pictures helps you become better aware of your practice. You learn about your crutches, you see the kinds of compositions you always go for etc. By working a lot and forcing yourself to actually confront what you are doing, you will learn more about what you actually like to photograph, as well as what you are now finding tiresome. Additionally, by forcing yourself to go out and work (or stay in and work!), you will find yourself in situations where you will photograph interesting things that you might never have considered before.
It is a tough exercise to do, especially when you have a normal daily routine as well, but it is very effective in kickstarting your creativity. I would also consider trying to photograph things other than events and flowers in bloom etc. Simply put, event photography requires events! They are not always happening...a garden has a lot of possibilities, but it is also quite easy to fall into the trap of simply photographing the same old pretty pictures. Why not try doing something you are not used to? Simple candids or daily life shots with friends or family? Architecture, food, still life, abstractions...there are any number of options that don't require particular times and places for them to work.
I actually was in a situation like this two years ago in November here. It was dark for 18 hours a day, cold, windy and generally miserable. I had to get out. I just got into the car and fled the city. I came upon a crazy display of streetlights in the snow. I got out and photographed for three hours. That started a series that has now led to a solo exhibition at the National Museum of Iceland...all because I was stir crazy and just went out to photograph SOMETHING!