FI has a group of people he was friends with in HS. He is still really good friends with a lot of them, but some he only sees once or twice a year. Recently, there was some pretty serious drama between two of them. G (who we see 1 or 2 times a year) came to us and told us S (who we see about 5 times a year) had a drug problem and he ripped him off blah blah blah. This prompted an intervention type thing which essentially got S into a program and clean. However, once clean, S told us G had a problem as well, stole from him and beats up his gf. Now in the meantime, G and his gf were living out of their car (reason still unknown) so Fi and I gave him our landlord's # and he now lives in our apartments. We haven't talked to him since but we did send them a save the date. Flash forward 2 months, our landlord is telling us that he is getting complaints from neightbors that G is beating his girlfriend and there have been some other incidents with threats to neighbors. I also know that S will freak if he sees G. We kind of had no idea when we sent the STD that G has apparently gone CRAZY. We do not want him at our wedding and know there will be problems between S and G. Do we just not send him an invite and leave it at that? We haven't talked to him so I am not sure calling explaining it is an option. WWYD?