To Post or Not to Post

That is the question I've been asking myself since I came up with this great idea for my book. On the one hand, I really would love to post it and get feedback on it before I ever go to a publisher with it, but on the other hand, I don't want it to get stolen, or if by some miracle I do get it published or even self publish it as an e-book, no one buys it because they find they can read it here for free...

I don't know, what would you guys do? I mean, I'd really love to get feedback on things like the plot and the characters and things that I'm not used to fully developing, and I'd love to let you guys get an inside look at it, the unrevised, pre-published version of it, but I don't know what to do. I know that it's a long shot to get something published, and it might be too long to post here because people may get bored with it waiting for new chapters and having too long chapters...

Seriously, what do you guys honestly think?

Would you read a story on here that's meant to be a book and possibly has long chapters and maybe a week or two in between posts?

What would you do if you were in my position right now?

Thanks in advance for listening guys. I seriously love how helpful and honest you guys are without being mean or judgemental.