I need you guys.... sadness

I don't have any good answer for you, just commiseration. I start to get down on myself a lot too! I think my writing is good. I'm sure it can improve and I'm constantly working on it, but when I read it it seems good to me. Friends and writing group buddies tell me it's good too. So why can't I sell a story? Who knows? It's so hard! I just keep telling myself that giving up isn't an option and keep writing.