Thanks for the help, I have already filed a claim with
www.moneyclaim.gov.uk and she has until the 22nd to respond to the claim. I have not had any response yet, and I know she is planning on moving away but I don't know when. I know that if she doesn't respond by the 22nd I can force a "judgement by default" in which I can request the money from her that she owes me. I can only hope that she doesn't move away too soon cos all this would of been a waste of time and money.