"
I could stay inside if that's what you want
I won't say a word for a day or two.
When I'm in my room I know what to do about you
Again, being submissive to his wants and needs from her. Letting him have whatever he wants, even if that means more space. "When I'm in my room I know what to do about you" implies that she knows she has to completely let her ex go, although because she's also implying submissiveness, she's reluctant to actually go through with him being out of her life.