I'm with mgarvey, Jon. Plan out what you want to say, even to the point of writing it down, and put it to her over the phone. Meeting her in person could be risky--she might be trying to have it both ways--to keep her current love in his #1 spot, and to have you on the side as well. Do you remember all those songs that say "If I can't be your lover, I'm not gonna be your fool!" This is the kind of situation they're talking about. If you meet her somewhere for a drink, you might not respond to her with your brain fully clear. I also think you need to reframe your description of her, from your true love to your PAST love--since she's with someone else, she's not being true--to you, anyway.

All the best,

Marymac