I use introspection as my muse to re-fabricate my life. Waiting for a catastrophic event is a bit morbid.
If you are dissatisfied to where your life is going, write down a list of things that would make you happy, regardless of any outside considerations.
When you have your list, no matter how large or small, begin to think of ways to achieve them, and then start to do those things.
Look yourself in the mirror every day and say, "I can do it."
Do something immediately that makes you happy. Re-arrange the furniture in your house, re-organize the kitchen. Get a plant. Walk around your neighborhood and take pictures of places that mean something to you, or that you find interesting.
Define what it means for you to be happy.
You don't snap out of a rut, you drag yourself out with the very threads that hold you in this life. It's never easy but it's ALWAYS worth it.
You can do it!