I do not use Facebook, based on a long-ago request from my "kids". They are all adults now, ranging in age from 23 - 28 and have been on Facebook since high school. Back then we sat down and discussed the pros and cons of the internet and specifically Facebook. I trusted my kids back then and I trust them even more now. They requested that SWMBO and I not join Facebook so that they could have their privacy. We went along with that request.
All 4 have my kids have become productive adults and, more importantly, good people. The boys have very good jobs, one daughter just earned a dual-Masters degree and found a great job even before she graduated. The other daughter will earn her Masters in 2017 and is already working in the Senior Living environment, building programs to enhance the lives of *us*, as part of the aging population.
We talk all the time via phone, email and text. We are all on great terms and they have always respected our opinions and advice. We let them have their Facebook space and it has worked out just fine.