I read your sitch and completely understand how it feels to have a "possible" OM. It can be nerve wrecking. Just keep this in mind he is most likely giving her complete and unconditional validation on all her feelings. It's an unfair situation because all he has to do to win her over is validate despite the true consequences. "He won't let you buy a new car because he says you can't afford it? How dare he! If it was me I would be ok with it..." Remember though if he is doing this he is writing checks he wont be able to cash, because he himself may be creating unreasonable expectations. Which will favor you in the end. OM an OW are good at creating crazy fantasies to entice WAS out. Be strong, and let them implode on their own. It needs to be her decision to end it, you pestering her will just put them on the same team against you. His weapon is positive emotions and the promise of a happy future. Your counter is a happy present to be followed by a happy future. So put your chin up and be the happiest person you can be for yourself.