I can understand your situation. When I first starting reading books on screenwriting, most were in the tone of "I tried it and If I didn't make it, you won't either." I hate that. I'm hopefully making my first short film next year and to be honest, if I only ever do this one film or if I only ever complete what I write and they're never bought, I had a lot of fun doing them and I figure, what else would I have done with my time, if not write?