The other day, one of the agents I follow on Twitter (I forget who) asked a great question (I'm paraphrasing, but the point stands): Are you sending your pages because they're the best they can be or because you're sick of reading and editing them and just want to get "this part" over with?
Over the last week and a half, I've been rereading and editing my book. I have my reasons, and I'm not going to go into specifics right now, but suffice to say I NEEDED to reread the pages. What did I learn?
First of all (and I mean this in all serious humility) my writing doesn't suck! Is this book going to win awards? I have no idea. Will it be a bestseller? I can't see into the future, so again, I don't know. But do I want to tear out my eyes every time I pull it up on the screen? NO! I ENJOY reading my book.
There is a part of me that wishes I didn't have to read it again, but not because it's a painful process. I'm still in love with this book. I still enjoy sitting down to edit it. The story, the prose, the characters all make me excited! But even Harry Potter (which is one of my all-time favorite series of books and WAY better than anything I've ever written) needs to spend time on the shelf, away from my eyes so that I can return to it one day and relive the pleasure found on those pages.
What's the point I'm driving at? You should love your writing! Your ideas should make you excited. When you think about sharing it with an agent, a critique partner, your friends and family, you should be overjoyed! Just like when you told them about that great novel that inspired you to sit down and write in the first place!
If you get sick every time you sit down to go over your pages, there might be something wrong with it. I learned that the hard way with Defender of the Crown. And I didn't see what was wrong with that book until after I finished The Dragon's Nephew.
Make sure you're genuinely in love with your book. If that's not the case, maybe it's time to break up. You don't want to spend the rest of your life with a book you hate. Because you HAVE to read it at least half a dozen more times before it's published. You won't have any choice in that.