Hacked account
It should not be 4 days, but a few hours. Nothing else to do other than changing passwords on both game account and email associated with the game. I am sure Customer Support will respond soon. Good luck. =)
Actually it can take support up to 72 hours max. However in most common situations they react a lot quicker (within a day). The 72 hours is how long it can take them to handle things when it is really difficult (wich this isn’t unfortunally for them it is routine).
Assuming she is indeed hacked and assuming the worse this is the process.
a: file a ticket to report this and ask assistence getting access to your account back.
b: log in and check the status of your account.
c: If there is anything wrong (deleted characters, moved to different server, missing items, etc)then reply to the allready existing ticket with a request for an account restoration.
Keep in mind these restoration are only done when the account really was compromised. This restoration means your account is restored to a previous snapshot. This means your girlfriend might loose things she got on her own as well.
For now all you can do is wait. If she has access to things like a guildbank you might want to notify an officer or guildleader to temporary restrict her access.
Arise, opressed of Tyria!