Catfish

A lady I use to work with messaged me out of the blue. She is "talking" to 2 guys, both in the military. She came off as a complete tag/benefit chaser. She was asking about how the benefits were and how big of a house the would get and so on. I asked her what his rank is. She said Sergeant Major (she is around 40 so I figured he was close to the end of his career and could have made that rank). I asked how long he has been in, 10 years........ Everything she tells me screams he is a catfish. Nothing I say will convince her. She keeps saying she willingly to him about when he comes home. I guess he is in Afghanistan and is coming to her state to be with her for 2 month (another red flag. The army may be different than the Navy but it is very hard to get 60 days of leave RIGHT after you come back from a deployment). And the kicker is, she has only talk to him on facebook and only for a month. How can I prove to her that she is being scammed?