I know and the staff are doing their best to prevent terrible disasters like this. If you feel like another user has accessed your account, change your password immedietly and report your suspitions to a moderator.
If you do an extremely long and complicated password eg, '1234ChEcDSDJKEDBFfjwnhfghdsoj382/d';;;@:[,-0923&£!"$£%&%$"' then i suggest that you write it down somewhere secret or extremely private or you may face the risk of forgetting it; you never know, you could fall over one day and get majorly concussed and forget all of your passwords. It has happened to one of my friends before. He forgot his school password. He got concussed when i rugby tackled him really aggressively and he smashed his head against my knee.
back to the topic, if you don't want to take that risk and are too lazy to write it down then just do something memerable like your faveritte movie, using capitals and numbers. A fullstop is also sensible because most people don't use them in passwords...
use long password with numbers and different size letters, and don't tell your password to anyone, that's the only thing I can think of to prevent it
Is a long password really necessary for a free flash games website login? I agree with the don't tell anyone, but, even IF someone does hack your account, what can they -really- do?