Life purpose can be a to big thing to grasp for oneself and often just stresses oneself out. For some it can help for others it just hits the knee, our personalities are diffrent.
I would try out if you have hard time with this to ask instead, "what can i do with my time that is important?"
Either it be make people laugh through comedy, help people in diffrent countries, helping stray dogs, It dosen't have to be anything worldchanging, aslong it's feel important for you.
the angle in that question becomes easier to work with, and you won't stand that much in your own way
Good luck!