Stop beating that dead horse.
That's right, I'm looking at you. Don't ignore me. I'm that little voice inside your head nagging you about something not be quite there. And you're ignoring me. Or trying to. Well, I'm tell you to cut it out. Stop it, right now.
As writers, I think we all do this, whether it's in drafting or in editing. We may not always love what we've written. A lot of times we're our own worst critics. No, love is not our downfall. Attachment is. We get too close to what we're doing and we say, but it has to be this way. You got that idea in your head and your going to stick with it. You're attached. And that's not a good thing.
It's okay to let things go. You don't need to continually beat your head against something if it's not working just as you need to remember to let something go. Just because you want something to work, doesn't mean it's going to. In fact, it will only waste your precious time and hurt more in the end.
I was writing yesterday (shocking, I know) and I started a scene that I loved. It had a fantastic first sentence and a great moment of understanding with the character and I was so excited about writing it. But, about 500 words in, I realized that this scene had no overall point, it only had small points that I can add later. It wasn't moving the story in actuality, so I had to let it go. And I did. With a small pout (because I can't just let things go just like that) I stopped working on that scene and went to the next, realizing that it was the next logical step in the story arch.
That doesn't mean we can't go back later and add it if we need to. That doesn't mean it's a great moment that belongs in another book. But you have to learn to know when you should stop. It's hard, but it must be done. So go. Do it. And give yourself a cookie to make up for the pain.