Wow man, I feel your pain, and this is a tough one. You are borderline one-itis but I'm glad you're taking the time to think about this reasonably.
How about the Push-Pull techniques? Lol. J/k. I think it might be best though to let her go as a g/f and show her you're able to move on but that she's important enough to you that you'd rather keep her by as a friend regardless of the current situation of your relationship. She probably feels used and the only thing that's gonna bring back her trust is good honest friendship, (w/o sex). This can take a while, so be patient.
Being she lost her virginity to you, I think she's gonna be very sensitive to anything you say or do, and for the next few relationships very un-trusting. So just be there for her, and since you're only partially one-itis, go out and get less than the recommended 12 girls. Inciting a little jealousy might be good, but don't be too drastic. She's already traumatized.
Good luck man. Keep us posted.