Thats F'd up man. Its all fun and games til you bring my family into it. I had a guy post up my address and a google pic of my house. I replied with a pic of me on the porch with a AR15 and "say when". He shut up pretty quick.
Had another say Im a registered sex offender. I told her to post a link to my name and address listed on the registry. She posted a "Joey Jones" (for those that dont know, my name is Joel) that lives in the next town over, and claimed I was using an alias and fake address. I just turned that one over to the cops.
Had another guy show up at my office running his mouth because I called him out for letting a dude (wanna be chick, got caught taking a leak in the bushes with his pecker out at a PDGA tourney and is barred perm.) play the womens division in his DG tournament. He proceeded to harass me, threaten me, and say Im a shitty Christian before showing up at my office. The boss just asked him why he was letting a dude looks like a lady play the womens div lol. Turned all the messeges over to the charity he was running the event for. They dropped him like a hot tater! Turns out the dude looks like a lady is his S/O.
FB is a crazy place. Ive been in FB jail more times than I can count. Just came off one for saying abortion is murder. Apparently its hate speech.
Id personally either handle it in person, or turn it over to LE. Thats nothing to play with there. If you need a hand, Im game.