First of all, I would like to offer you this hope: no matter how awful you feel right now...no matter how much it feels like you will never get over this and be happy again... You will. When my H's affair came out, I felt like my life had been destroyed by a nuclear blast. The pain and grief was overwhelming. I felt like I was walking around in a daze...observing everything in my life, but not an active participant in it. I was triggered by the tiniest little things. Not only was my future permanently altered, but so was my past. I couldn't even look at our family pictures without imagining all the things I didn't know that had been going on at the same time. I felt like my entire life had been a lie. But it gets better. It's not a short road, and definitely not an easy one. But, with time and distance from the situation, healing will come. I promise.
Although in my case it was my W that did the cheating, this is exactly how it was for me too...right down to not being able to look at pictures or remember kids' ball games and stuff for months because of what I now knew was likely going on when she left to 'run an errand' or 'go get groceries'.
I can also attest to it getting better.
I also agree about loving and forgiving, but I highly recommend you do that, if/when you are able, working through it with an MC who is practical, believes in M and only advocates D in an extreme situation as a last resort, and has experience helping people through this with some success.
Trying to deal with infidelity and continue the M without pro help is to me like trying to diffuse a nuclear bomb because you know how to repair refrigerators. That's fine if it's all you got...but if at all possible, you really need someone who can guide you through it and knows what to do.