You have a ton to talk about. You can never fault someone for pursuing a passion and plenty of people fail. You number 1 focus on you application should be to show how these experiences have shaped the leader you are today.
Why did your business fail?
What did you learn?
Are you returning to school to get a better understanding of how to manage certain portions of a new venture? Find fellow students to collaborate with?
Just remember that your application is intended to bridge the gap between what you did before school and what you plan on doing after school - you are not expected to be perfect now. Describe how the business school experience will help you connect the two parts of your life.
If my response helps, please add throw me a kudos.
Jim Kernan is the Director of GMAT Operations at Stratus Prep and author of GMAT Materials for GMAT Prepster.