Ok, so she's in a house with a room and likely not paying cable, taxes, water, utilties, etc.
Based on that, I stand behind the email suggestion I gave you. You still are likely paying at least a couple hundred more per month than her and as you said, you didn't move out.
But keep it professional, not accusatory or whiny and leave out the whole you moved out part, she knows she moved out. She is trying to guilt you into giving in.
Your whole thread is be strong, go dark, see if she misses you and comes to you, so stay strong on this monetary issue also.
You couldn't guilt her into staying (I know, trust me) so don't let her guilt you into giving in, it might help in the long run.
TBL now equals "Toward Better Love" M-44 W-42; 2 kids; married 11 years 1st bomb 10-08, reconcile 12-08 2nd bomb 8-09, moving toward reconcile 3-7-10