Lyric discussion by missme 

Cover art for December Baby lyrics by Ingrid Michaelson

Such a beautiful song. I think it's about the fact the other person's moved on ("your eyes avoiding mine") and you're trying to catch up with them, but can't. It's such a horrible feeling when you know the other person doesn't feel the same way anymore and you want to make them, but can't. "You have had your fill, your fill of me" is about the fact he's done with her, he's got what he wanted from her and is now ready to go.

Also, I reckon the juxtaposition in the lines

"How can I catch up when I don't don't want to? How can I catch up when I still want you?"

Is that she doesn't want to catch up with him because she knows it's a bad idea because he doesn't want her anymore, yet at the same time she wants to catch up with him because she still feels the same way... But it's not a good idea.