Lisalisa, on the relaxed about leaving your house front, that would disturb me.
Could you give her a gentle reminder by offering to drop her off on the last day? And ask her how many bags she has to take with her. Remember to take the keys off her. Change the burglar alarm code.
I think that would be a good policy actually to 'escort' her out of the house seeing that you have suspicions about her thievery. If you have not barred overseas/premium number phone calls, I would do so and call the phone company to check unbilled phone bills. Hide/lock up all jewellery, cash and valuables. Do a quick recce before she leaves - eg all laptops, tomtom accounted for.
I admit I am a bit paranoid. Once I have sacked someone who is live-in, I would rather pay for them to leave asap, than have them serve out a notice.