I know it might be scary, but I think you need to tell her the truth ASAP. In doing so now, it may bring things to an end as you fear. But chances are, it WON'T scare her away and you'll be starting this new relationship on the right foot with nothing but honesty.
Keeping it a secret for a while longer may give a short term benefit, but will most likely not end well when it surfaces.
We are all learning to better ourselves - so be the best Cam you can be and be HONEST and not start a new relationship built on deception.
Me: 43 W: 37 Together: 18 M: 15 D: 8 yrs old ILYBNILWY: March 2011 She Filed for D: August 2011 She moved out: Sept 1, 2011 Reconciled: May 2012 Divorce Case dropped: July 2012