I said in another post how essential editors are. And it's true. But you have to trust your own judgement sometimes, and sometimes you will be in conflict with your editor. There is no easy answer to resolving the conflict - I'll say that probably Most of the time the editor will be right - but here is one experience I had, and it convinced me that I should stand up a little more for my writing.
I had an editor who read my book and loved it, then worked on it extensively with me - calling me (over here in France) brainstorming with me, giving me her ideas, and taking out things that she idn't like personally...)I was flattered and didn't know better, so I went along with it. The editor put in a lot of her ideas. Afterwards the book came out and did all right.
But I read it again, and it just looked flat to me. The parts in my book that I thought were strong displeased the editor and she had me cut them - not because they slowed the story or anything - but because she didn't like them. It's hard to explain, but she made the book bland. After that I've been leery of brainstorming books with editors. I'd rather they just concentrated on editing. Sometimes it's better to have something that someone will either love or hate, rather than risk ending up with something that everyone likes...
Likes is the kiss of death.