It is truly excellent to have someone believe in you and your ability to write. But I think it is just as helpful to have people who don't believe in you, people who mock you, people who doubt you, people who enrage you. Fortunately, there is never a shortage of this type of person in the world ... write for yourself. Write for the story. And write, also, for all of the people who doubt you. Write for all those people who are not brave enough to do this grand and wondrous thing themselves. Let them motivate you.