If it happened to you, your actions, no matter how small a part that they played in the outcome, are still a part of the outcome; so take that portion of the responsibility without hesitation. Did you not market your business, thinking, if you built it, they would come? Did you not focus on client retention, when business was booming? Did you not sell value, instead of price when asking for the sale?
There are many factors as to why things happen the way they do. Some of your own actions account for it; some do not. No matter the "what ifs," remember that sitting around and wondering about them will only displace your time and stop you from changing your situation. Stand out of the crowd, accept your situation, and stop questioning, "Why me?" and, "What if?" after you commit to an action of change to resolve the situation. Only then can you execute a plan to change within.
No matter what, you and you alone have the ability to change your situation. It may not be immediate, but change will happen with an executed plan from a person who has first accepted the reality that it is only their actions that can improve this situation. Taking responsibility for actions in your life is a big step to turn your situation into success.
The difference between success and non-success is in an individual's ability to believe in themselves as their own element of change and the daily commitment of that individual with that knowledge of success to execute those changes.
So, are you going to take action today? Good, now finish reading this and implement.