How to deactivate a PSN account on a PS3?

Solution 1:

Is there a way to delete her PSN account from my PS3 account without losing anything?

There is a way to remove a user from a PS3 console, but you will lose the following:

• Paid Content Downloaded from PlayStation Network
  • The account that bought the content can still download it from another console
  • Your console however, will be unable to use the content due to missing licenses (in other words, the license that allows the content to be used is tied to her account)
• Messages Sent and Received
• Internet Browser Bookmarks, History and Settings
• Game Data for PS1, PS2, PS3, PSP, PSVita, PC Engine
  • Save Data can be backed up to a USB Drive (all) or PlayStation Plus Online Storage (PS3, PC Engine and NEOGEO only)
• Words from the Predictive Text Dictionary
• Keyboard/Mouse Settings
• Voice Changer Settings

If you still want to remove the account from the console, you need to:

• Log in with the user that you plan to delete
• On the XMB, go to the User section at the far left
• Press Triangle to open a set of options
• Select Delete to remove the user
• When you see If you delete the User, saved data for PlayStation 3 format software, message, trophies and other information will also be deleted. Are you sure you want to continue?, select Yes
• Done!