Oh and PS: I think that her 'wanting to talk about it on Thursday' is a clear indicator that your foot is in the door. If she were honestly happy with her fiancee she wouldnt be 'meeting' you to 'talk' about an 'email' you sent her.
She wants your junk man - dont blow it - let her feel like shes in control of the situation - let her talk and only open your mouth when youre asked a direct question. Always answer those questions with direct answers; Yes, No, Absolutely work... "I think... I guess... I love... nah... nevermind..." will make her clam dry up quick.
In any event, I dunno how comfortable I'd be in a relationship with a girl who flirted her bellybutton off and/or screwed around with another guy (you) while she was engaged. Fortunately for you, lust is much more applicable than love in this situation.