I face similar problems with my characters. Right now, in the chapter I am about to start, a character is going to wake my heroine up. I want it to be one character doing the waking but my muse thinks it should be someone else. Now, I, Rebecca Royce, the writer of this piece of fiction, knows its important for the character I want to do it to wake up my heroine so some pieces of information can be given out and some story points worked through.
However, my muse has a different vision for the chapter.
It begs the question: who is in charge of this story? Of course this isn't different from real life, who is in charge? Me, who wants my son to play soccer or my son or wants to come home and watch cartoons?
Sigh. We'll see on all counts.