Infidelity Support Group
Any relationship in which one partner engages willfully in sexual relations with another outside of the partnership is considered to have experienced infidelity. This breach of trust is often traumatizing for the faithful partner as well as the relationship, and support is often needed to heal emotionally and to decide whether or not the relationship should continue after...

If you are struggling emotionaly you really may need to find new methods of healing. Ic, praying, reading books and mc are some ideas. Time stamp no. But hopefully you can progress forward and heal.
Though this is sometimes hard for me to accept, I've read that the BS can take 2-5 years to fully recover from the devastation of an A. According to that, you haven't even reached the minimum time yet if you're at 21 months. I'm barely at 18 months and I still have moments like you describe. I'm happy to say they are fewer and more far between but when they hit, you would think that the A happened 5 minutes ago with the power they pack.
It takes time. My H has also wondered aloud whether or not I will ever get past this. Ironically, I think that most CSs are looking for some sort of reassurance that if they do what they're suppose to do, this will have a happy ending. Since they brought this on however, part of their role is comforting you through those tough times and living with the uncertainty that it might not end the way they want.
You both have to understand that there is 'no date' you can put on it. Ask yourself this question: If you look at the big picture instead of the day to day routine of" two steps forward, 1 step back" is your overall progress going forward? If it is, then you're heading in the right direction.
Sending you support
You will likely never trust him like you formerly did.
You will likely never feel the same way toward him.
This does not mean that you can't have a good marriage. You must decide if you can accept what happened.
He cannot undo what he did....it's impossible.
I still feel like a victim of some cruel joke. But this real, this is my reality now.I have to learn to deal with it. Put on my big girl panties and plow through this mess!
My fairytale is gone and it will never be the same. Thats life and we all know it can be so unfair. Thanks again.
Good luck with whatever you decide. Whatever you choose, go with is full-force. When I knew that being disrespected by my X's affair wasn't ever going to fly with me, I went with the divorce full-force. If you choose to stay, then be willing to truly stay and find a way to gain acceptance that he DID do this, and yes, now you know he really is the kind of man capable of doing this.
One issue that my husband and I discussed often with our MC is that forgiving doesn't mean forgetting. This was a very difficult thing for my husband to accept, to know that he could be forgiven but that his affair would always be a part of our marital history. Not the only part, not the defining part, but it doesn't disappear and it can't be undone. That said it doesn't mean that you can't move on, recover and rebuild, and be happy together-- especially if both parities want to . And it seems like you both want to. I do recommend counseling, if possible. For us it was a good, safe venue for discussing the really hard and painful things.
Your fairytale comment really tugs at the heartstrings-everyone thought we had the perfect, fairytale marriage and that my husband was a prince. While it is devastating at first to have your fairytale shattered, the problem with fairytales is that they are fiction, and real life is decidedly non-fiction. Though I would never have wished for an affair to destroy our fairytale, our marriage is stronger and more honest now. But it took me a few years to get to the point were I could say that -- you are just beginning the process. It's too soon to know how it will turn out for you; too soon to know if you are married to The Big Bad Wolf, or to a good guy who made a Big Bad Mistake that he now regrets with all his heart. Don't worry about doing the wrong thing, just give yourself the time to figure it out.
It does get clearer, calmer and better as the days pass.