You do have a purpose you just haven't found it yet. I'm 30 years old and I'm just finishing college and in a position to be promoted. However before I flunked out of college. I was fired from a job because of behavioral issues. I was suicidal at two different times in my life. The only reason why I didn't go through with it was because someone told me my life was worth it. Life is going to be hard. Sometimes it's going to be hell. But you have to believe your life mean something and it does.