I kinda get Alice's perspective. This dude you were engaged to, and probably a bit excited in meeting, never payed attention to you, continued to ignore you for years, and in the end, severed the little connection that existed between you two. All the while she was a kid, probably hoping for someone that she could talk to and be friends with.
Now, that guy is doing a total 180 and trying to be nice all of a sudden. Naturally, she would be suspicious.