Hi, JMW.
Your situation isn't exactly like mine in that I am a FWW and have been out of my PA since end of May, NC since June. But we are similar in that not so long ago I was unsure of what to do in dealing with my betrayal.
I came here when I was struggling with whether or not to tell my BH about my PA. Through the encouragement, tough talk, and support of the wonderful people on this site I sucked it up and did what was the right thing to do -- I confessed my PA to my BH over 2 weeks ago. You may not like the advice you get here, but you really need to take it. I am dealing with the toughest stuff right now that I've ever dealt with. I have exposed warts and things in my closet that I didn't even remember existed. I'm in very early recovery with my BH right now. And we're struggling. A lot. We may not make it, though goodness knows I'm trying. But whether or not we do, for the first time in months I can kind of sort of look at myself in the mirror, because I am finally being honest with my BH, with those closest to me, and with myself. I feel dirty and ashamed, but I am slowly trying to restore a shread of dignity by telling all.
Tell. Please do. Eventually he will find out and I promise you, the sooner is definitely the better. I have a very long thread going on here about my journey, one that started when I was still debating whether to confess and continuing through to this evening. It's under "Recovery" and is titled "Hubby Now Cares. Should I Tell of A?" Learn through my journey. You may think it doesn't apply to you now. But I promise you it will. I betrayed my then boyfriend over 16 years ago and it's now back to haunt me because I didn't admit it then.
Keep posting, listen to the very sound and proven advice you get here, read and believe Dr. H's wisdom in his books and on this site, and most importantly be COMPLETELY honest.
Take care, JMW.