Two weeks ago my game was always shutting down, i was also getting allot of lag problems. it was frustrating. I read in the forums that other players this too.
Now this is not a fix for everyone, ok. im just letting you know that while i thought it was the game doing it, i found out it was my modem. I replaced my modem and not a single problem since. I have a standard modem with Bigpond.
Sometimes you have to look at all options before complaining.