You must not be that interested in staying in contact with your family if you're only willing to use one, specific way to do it and simply refuse to use any other method.
My mom lives in a different country, is retired and can very easily use Signal to msg me and do video calls. She has no technical education, and is not very good with the devices. But... she could install Signal and use it every day.
TIL. I haven’t been on Facebook in so many years that I didn’t know this. Still, given how many good alternatives are out there, it doesn’t seem like a good reason to keep using Facebook.