How do I keep my iPhone private off my other Apple devices

Question

I have three Apple device; one iPad, my iPhone and my wife's iPhone. I set up all three of them using iTunes, and they are all linked to one Apple ID.
The issue that I'm having, is that all three devices are trying to iMessage and FaceTime, using my email and both of our phone numbers. I already went inside The settings of each device, and made each device to only use the phone that corresponds to that iPhone, and, in case of the iPad it will only FaceTime using my email address. But the phone numbers are still there and I don't want to have, in my case, access to my wife's messages.
I want each iPhone, and the iPad to be separate and private, but I don't want to have to create three different Apple IDs, because we share music in all three devices.
I don't have any phone number registered to my Apple ID, so the iPhones are getting their numbers off of the carrier activation, not the Apple ID.

Answer 1

Cleanest solution is get new, different AppleIDs and use those for separate iCloud, iMessage and Facetime accounts on all three devices.
You can still use the single shared AppleID for all purchases in the iTunes and App stores.
You can have as many AppleIDs as you wish, and you can use a different one for each Apple service if you wish.
So, just get some free gmail, hotmail, aol or whatever email accounts and set up some new AppleIDs.  Then set up unique iCloud and iMessage accounts on each device.