Be prepared for a massive shit storm! She may very well be able to deal with the whole concept of poly, but NOT the fact that her bf has been cheating on her for nearly 2 years. Getting over being cheated on take YEARS! No, it's not impossible, but it is extremely difficult and requires massive amounts of effort on every ones part and groveling by the cheaters. Take a look through LovingRadiance's early posts and her blog
. Don't let yourself think that this can be fixed with a bit of yelling/screaming and a few days of tears, it won't. The hurt, anger and feelings of betrayal will keep circling over and over again.