Put aside your ego—and it may be difficult to do that. Whenever the edit comes back from my editor, I don't look at it for a day or two. I focus on preparing myself to be objective about the editing.
It's not easy to have some unknown person say, in effect, "This is dreadful," but we may need to hear that message. However, I've never had an editor actually write such words.
As I ready myself, I say to myself many times during the day, "I accept the editing objectively and dispassionately." At some point, I know I can do that and then I'm ready. I prepare myself to accept the worst criticism possible, and it's a relief to see that my worst anxieties were just that—anxieties.
It may help if you remind yourself that editors have their reasons for making suggested changes. They're not always correct, but they read your work with a fresh and objective perspective. Sometimes editors will raise a question I haven't thought of, and I'm grateful because it makes my book better.