Critique partners are some of the best people you'll ever meet. They put their work in your hands and in return try and tell you- as nicely as possible- what they think of your own. It's definitely a give and take sort of relationship but at the end of the day, that person is taking their time to read your stuff as well as work on their own.
A good critique partner doesn't shoot you down, or tell you what you're writing is terrible, they tell you what they love about it, sandwiched in with the things that need improvement. They get into your story as much as you do, and they hate/love/cry/laugh right along with your characters.
A good critique partner is invaluable.
Having said that, I think it's also important for people to remember that a critique partner's job is to give you their opinion. As in, how they personally feel about your novel.
Testing out a critique partner who comes back and says they don't like your story is no different than someone picking it up in a bookstore and putting it back down. It happens. That's why there are billions of books, and hundreds of genres- because not everybody likes the same things.
The most important thing is that your novel is exactly what YOU want it to be. A person can tell you how to make it flow better or where things slow down, but they can't make it any more yours than it already is. They're always going to be your characters, and your settings.
So just keep this in mind when/if you're out looking for someone to give you a little feedback. If you don't agree with what they're telling you, don't change it. If taking out what they're suggesting removes a piece that you really love, leave it in, but do it objectively. There's always room for improvement, no matter what stage you're in, but it's still your story.
And please, above all else, remember that you are intelligent, and creative and amazing, and nobody could ever write your story as well as you.