Gabriella,
Reading between the lines (well,okay, it was obvious) you do want out of your marriage. The other posters are right. You have to decide to be faithful to your husband, or to leave him.
Of course the other guy is a player. But at the same time, maybe he is thinking two things:
1. there's no chance with this Gabriella, she's too faithful to her hubby AND
2, I'm a terrble person to have kissed my friend's wife, I can't face him again, I feel like a jerk.
So he doesn't hang out with you guys. Do you actually think you can ever have a normal relationship with him agaiin? no.
And as to the kiss on the cheek vs the lips, honey, he was just flirting. Had you given the green light, he would have kissed on the lips.