Ive been plagued with this since my last update and like you, I take exception to people who say, just don't share the same account. I've shared the same account across all of my family's devices for years, so this is an apple issue and not just a settings issue. I've been tinkering with settings, including handoff and answer calls on other devices and despite ensuring these are all disabled, then a bit of head scratching, nothing appeared to work. However, I've just gone into the settings on all of my family phones and under both FaceTime and iMessage settings, one or more were using the Apple ID. I have now disabled this on each device, so that only the single phone number for each device can be used for FaceTime and iMessage. I tried calling between three devices, so phone 1 called phone 2, phone 2 called phone 3 and phone 3 called phone 1, and it would appear the call history is now showing correctly, one call out and one different call in, on each phone. Hopefully that's solved it, but with Apple, it may only last until the next update ! Good luck all.