This was weird. Really weird. After Gray's bitter words about not being able to find anyone even though he wanted to settle down, Aaron fully expected that this woman would be in it for the money. People didn't up and get engaged when they weren't even dating someone a week ago.
And as much of a phony as Gray was, he wasn't good enough of an actor to feign jealousy and desperation. His acting was the kind that made him seem more pleasant than he actually was. That day in the restaurant had been one of the rare moments were his real feelings slipped out for a moment.
Aaron had figured this entire thing was a farce and that Gray was desperate so he settled for the first person who came along. It wouldn't be the first time that someone had offered money to have the kind of relationship they wanted.