That love/ hate thing

I'm reaching the end of writing my third book - a lovely book called 'Jumping in Puddles' set in a fictional Donegal village where four lone parents come together to get their lives back on track.
Except at the moment I don't think it is lovely. I think it is a pain in the bum. Writing is not all about sitting down at the keyboard and seeing the words flow forth faster than your fingers can keep up. Sometimes it is about writing the same sentence 15 times and still not getting it right. Some times it is about trying to inject humour but finding it all smacks of trying too hard. Some times you feel as if you know your characters as well as if they lived in your house and ate your biscuits and other times you struggle to relate.
Now I could just batter the rest of this book out - one word after the other - but unless it is honest, and funny and as good as it can be, I'm not interested.
So while I think it is probably the best book I've written, it has also been the toughest writing challenge to date.
Still, 28,000 words to go...(x 15 for the rewrites). Shouldn't take too long??