I agree with a lot to most of what has been said, the problem is I remember this. I remember the NRE, the feeling that it can all work out and so you just really don't hear the negative. So I'm going to try and help you put things in perspective. See, a lot of people have started their road to poly with cheating. So it's not that people are being judgmental, or looking down on you. Most of the advice you are getting is probably from a perspective of 'been there done that try not to crash and burn as I did.' We just aren't always so thrilled with reliving the hard parts. So here goes.
My husband and I are both in our mid thirties. About four years ago, I had an affair. Oh I didn't call it that of course, and it was emotional, long distance. I never slept around, I didn't end up in bed with someone else. The betrayal of my husband's trust was no less a betrayal because of it. I am only pointing it out because that's where things differ. Husband never had to worry about picturing me in bed with someone else and the proverbial laughing at how stupid he is for not knowing. Otherwise, all the same.
Sure, right now you are thinking, hey they got along before and were friends! We were all living together technically and it was good! Why can't it be that easy? Well, it can't. You love your wife, great, cause you'll need to remember that in the time to come. We spent years rebuilding trust. I had to be an open book. He read any emails I got if he wanted. Saw any IM messages I got or sent if he wanted to. We had much much discussion and yes I had to take a lot of getting yelled at. A lot of cold shoulders, a lot of pain directed towards me. Some of it, maybe a bit too harsh, but I caused the hurt. Sure I can't be responsible for other people's emotions, but when I've hurt someone, I AM responsible for that hurt. So, the relationship that was the betrayal? Did not last. Couldn't. For various reasons, the fact that the people involved were also betraying my husband and he didnt' even know them was a big part of it.
Your wife and this woman WERE friends. You say it as if they still are. They aren't. Trust me. If anything your wife may just be thinking this woman PRETENDED to be her friend while sleeping with her husband behind her back. That. Hurts.
So yes, there will be work to repair the damage in your marriage, and rebuild trust. Now here's the really unpleasant truth about it all. Even if, years later you are finally in a good place. There are more good days then bad even as she adjusts to being in a poly relationship. Which is what you are going for even if she remains monogamous. There will still be bad days.
It's four years for us. I'm in a new LDR. Most days, are good. I can talk to DH about my boyfriend. He asks, he sees us face timing or on the phone. There's a twinge but otherwise it's good! Now he is on a list, or a forum for poly people, or mono and poly people. He sees a story that reminds him of that betrayal four years later. It's now a bad day. It's all fresh and new again. The pain, the betrayal. The work we did rebuilding trust? it's there, but fresher, more painful and at the surface is the cheating wife who hurt him.
So you can be upset that people are judging you. they are trying to help you. If you can't even own up to the fact that you cheated, betrayed your wife, and continued to do so, only admitting it when you wanted to keep both relationships, then you haven't even begun to rebuild trust or heal the relationship you claim to want with your wife. It's harsh, it's hurtful, but sadly, it's the truth. Moving on from here? Sure, someday. When you've gone back and worked on the hurt. Too often people assume once it's out in the open then it's fine. Not fine. Two years. She doesn't see it as two years she didn't know, she is going to see it as two years she was lied to. That's a lot of pain. Acknowledge it. Own up to it. Understand there is not going to be a time where that no longer matters for a long, long, long time.