I got a divorce and need to change my Apple ID

See the following: Change your Apple ID - Apple Support

Note that if the "@mac.com" part of your example is real, see the "How to change your Apple ID if it ends with @icloud.com, @me.com, or @mac.com" section in that link.

Also be sure to note the following from that link:

Before you change your Apple ID

Sign out of all Apple services and devices that use your Apple ID. If you want to use your iPhone, iPad, or iPod touch to change your Apple ID, stay signed in with your Apple ID on only

that device.

You can only change your ID to the @me.com or @icloud.com versions of the address, which will still have the same text before the '@'. The only way you can change the main address is to get a completely new Apple ID,, which will cause you a lot of problems.

However, though you can't change the login (which no-one else sees) you can change the email address you give to people. You can add up to three 'email aliases' - these are additional addresses (not accounts) which deliver into the same inbox as the main account. (In fact it's a good idea to give out alias addresses, rather than the main address, because if they attract spam you can easily change them.)

You should be aware before you start that once you've created an alias you cannot turn that address into a full iCloud account or move it to another account.

More information on aliases here: https://help.apple.com/icloud/#mm6b1a490a