Hi chryso!
I'm assuming that you both have your own accounts and aren't sharing one? Outside of just communication with her and letting each other know which realm you played last, there is currently not a technological solution to this problem. Perhaps you could adopt a procedural solution?
1. If you both are home and want to play, decide which realm and how long it has been since you played to ensure you don't run afoul of the realm timer.
2. If one of you is not home...
- If you both only play from home, this might be easy to ensure -- just knock on their door and ask! If either of you plays from elsewhere, though (work, school, internet cafe, etc.) then you will have to call or communicate with them to make sure they aren't online.
Very Important! Make sure that the other player is not currently logged into their account!- Log into their account and see if their realm timer is expired (or use a different method if you don't want to actually log on -- see the ).
Realm Switch Timer FAQ- If the other player's realm timer is reset, then you are safe to log into any realm you want from account. (Of course, if you wanted to change realm then your timer will have to be reset as well).
your- If the other player's timer is set, then you will have to play on whatever realm they are currently bound to, or wait until their timer is reset to change. Also, if they are bound to a different realm than you last played, you might need to wait until your timer is reset before logging in to avoid being auto-logged into a different realm than the other player is on.
Another way you could do this is to go old school and leave sticky notes on monitors about which realm you played and the time you logged off at.
Maybe an enterprising developer could write a utility to help people manage which realms have been logged into by peer machines to help people manage schedules? Interesting use-case... definitely something to think about!
Hope that helps!