Can not lie I thought the same too ... or at least to a point she is just playing along with the fantasy to get her kicks.
Or... maybe not originally a scam, but definitely playing along to take advantage of the sitch in order to get the green card and eventually citizenship. Like -- perhaps that wasn't her intention to begin with, but once the ball started rolling she saw the opportunity and is pursing it since the opportunity is there.
Me 48, Her 50 (Same-Sex Couple) 3 Children Together: 9.5 years before BD BD: Week of 10/27/14 ExW started EA w OW 9/2014 ExW married OW 12/2015