If you have a physical disk AND an active PS3 code on your 1.0 account it shouldn't matter who's disc it is or if its downloaded you should be able to log into your account IF your PSN ID and SE ID match up AND there's a PS3 version of the game on the account (it should show up in your SE account and you should have entered a code to activate it) it is not based on the disk in any way its account based so if you used the code that came with the disk on "SIS" then only her account will be able to play on ps3 so yes you would have to buy another disc (only for the code) and apply it to your account

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sorry if i've sounded grumpy don't mean to (and i do understand your frustration)