I am so sorry you are going through this. Sad thing is at this stage your DH has the power to enable you both to move forwards together, but he won’t be able to see this.
In my situation we had been together 17 years with 3 DC’s, the usual ups and downs but in the main a good relationship. At the time we were on a bit of a down. He went to his brother’s wedding in Finland and got drunk and maudlin. In the early hours a very pretty young girl started talking to him, he felt flattered, he paid her a compliment, she took this as a green light (as you would), they flirted, her taxi came, a hug goodbye turned into a kiss, he liked it. He walked her to the door, they snogged the face off each other and groped, she went home, he went to bed thinking what the fuck have I just done.
For the next 6 weeks he was weird, my gut told me something was up, I kept questioning him. Eventually he broke down, he said he had met someone he ‘liked’ in Finland and was questioning if he loved me. At this stage I still believed him to be trustworthy and honourable; I believed he was ending it with me for her. I found her on Facebook and said I was going to message her; he panicked and said they kissed. I contacted her; he panicked again and said they kissed twice, but no groping and certainly nothing sexual. He swore on his kids’ lives. It was nearly 4 months before he admitted the truth, he actually confessed to more than she did, but he doesn’t know this! He offered me full access to his phone, email and bank accounts, I had already and checked!
This was 2 years ago The damage was not really caused by that 1hr in Finland, but the lies, minimising and loss of trust afterwards. He understands now that he held the key for restoring trust, telling the truth - SIMPLE. At the time he couldn’t face up to his actions; he was frightened that each disclosure could lead to me ending our marriage.
With hindsight I would have asked him to leave for a while, to give me time and space to think clearly without him and to empower me to feel in control of this situation that was not of my making. I would have told him reconciliation was only possible if he demonstrated his respect and commitment to me full by disclosure. Whilst he was still in the home and relationship there was no incentive to release more information. In essence he was ‘getting away with it’. I would still have contacted the OW, however just remember that the OW is just as bad as him.
Ultimately the decision is yours, even if it’s a decision not to make a decision at this time. You are not letting the side down by considering reconciliation; it’s a long and painful road in many ways harder than breaking up. This is your life, your family, only you know if there is something you think worth saving, only you know if you are a forgiving person or the sort to be eaten away by resentment. You must also be prepared that you may never feel quite the same way about your DH and relationship again. I see a weak, selfish side in my DH that I never knew existed and at times I still feel vulnerable and guarded.
Try to take care of yourself, have long warm baths, do things you enjoy, read, watch nice things on telly, walk the dog/play sport, try to sleep, eat or at least keep your fluid levels up. You are not alone, there are so many of us who have trodden this path. The key thing to remember is that you will feel better again.