How to “unshare” an Apple ID
Since 2014, when Apple introduced Family Sharing, they have consistently discouraged sharing an Apple ID between different individuals. Apple IDs are personal; they shouldn’t be shared any more than you would share a toothbrush. If you share an Apple ID with someone else bad things can happen, such as intermixed messages, recent calls, voicemails, photos and other information that should be personal (your gift list, personal diary, or journal, for example).
Each user should have their own Apple ID, then you can create Family Sharing→What is Family Sharing? - Apple Support. That way you can share what you want to share and not share what you don’t want to share.
It is OK to share an Apple ID among devices used by one person, such as an iPhone, an iPad, a Mac, a Windows computer with iCloud for Windows installed; in fact, it is a very useful thing to do. But not between devices used by different people.
Here is Apple’s FAQ: https://appleid.apple.com/faq/#!&page=faq. See the 4th bullet item.
And here is Apple's expansion of what I've posted→Make sure that each family member has a unique Apple ID - Apple Support
But…What if you are already sharing an Apple ID with someone? How do you separate from this relationship?
It’s actually pretty easy to stop sharing, and switch to Family Sharing:
- If you don’t have a recent backup, create one on your computer or in iCloud (just for security, you probably won’t need it)→How to back up your iPhone, iPad, and iPod touch - Apple Support
- Go to Settings/[apple ID name] and tap Sign Out
- If you sync to iCloud you will be asked if you want to keep the content that syncs; say yes to each item
- Tap to create a new Apple ID
- If you sync to iCloud, go to Settings/Apple ID name]/iCloud and turn on the switches for items you want to sync.
- Log in to the same email accounts you had on the shared Apple ID if they have logged out (they probably did not, unless one of them was an iCloud email address)
Contacts, Calendars, Notes, and Reminders sync to email accounts, so if you are logged in you will still have all of them. You will also still have all photos.
Next, decide who will be the family “organizer” and have that person set up Family Sharing→Set up Family Sharing - Apple Support
You can share all previous and future purchases; here is more information on that→Share with your family - Apple Support
