I’ve had a fb account for 4 or 5 years now. I reluctantly got it because it was the only way for us to get messages back and forth from our foster daughter in Belarus. They are not allowed email there. It’s been a blessing we can send messages back and forth quickly and can set up Skype times. She is my only friend and somehow I lucked out and set up the security right to where I get no friend requests or alerts or emails.
If you are using Facebook for communication, you are not participating in their business model, and probably represent a cost to the company.