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...
Most cheating spouses don't divulge the worst of the details. Saying they only kissed is on the first page of the cheaters handbook, I think. Once you pry further, it changes to only a quick blowjob. I am not sure you got all the details of what happened back then, and that could be why you can't even kiss him, because deep down you think there was more but for yours and his sake, you want to believe it was only a kiss. If he didn't get it from her, chances are he found it somewhere else. I hope I'm wrong but on averages from what I have read here, the kissing part is only the tip of the iceberg, and the biggest lie going. If you think cheaters suddenly tell the truth once caught, you're fooling yourself.
I wish you well.