Dude, Where's My Muse?

So this has been on my mind for awhile. And when is it not a good time for writerly babble? Especially on a writer's blog :o)
Anyways, in working chat this afternoon I had a thought. Why is it so hard for us writers to go in and revise, cut out and edit our stuff? I'm having a huge time of it with Sabrina and its opening. I still don't quite know where the story's gonna pick up, whether at that point she knows of her gift yet or not...but every bit that's there its hard to look at and go this just doesn't work. Why? Why the heck am I so attached to something I know isn’t right for the story. That though it would advance the story forward just doesn’t point blank FEEL right? And why the heck doesn’t the right part come around the first time?
I’m not cutting anything out yet, I just keep adding to the file waiting for the right bit of inspiration to strike with the right thought, the right scene that’ll make me go ah-ha! And make all the editing SO much more easier to handle.
So to the writing muses out there, I’d like a brand spanking new opening that feels right to me. Oh and a timeline that’d be great!!