OP, I don't think you're coming back, but maybe you'll read this, so I'll type it just in case.
I've read the thread from nearly three years ago and this one. I have a feeling that the person you're married to is manipulative and probably gaslighting you, convincing you that things that seem bad aren't bad because he would never be like that. He would never cheat on you, he would never deliberately upset someone, because after all he is a kind, caring and compassionate person. But he's not is he?
You didn't come back to the escort thread to tell everyone how it all turned out in the end, but my guess is that eventually you decided to believe him and he knew you would. He knew you wouldn't contact his office because of the alleged sacking before he started working there, meaning that if you contacted them he might get sacked too ... and of course he made himself a poor victim of being misunderstood and "Oh I know you will leave me, but I'm a good person, I wouldn't do that .." blah, blah, and blah.
He's made you believe he is a person he isn't and I'm sure that since then and now there have been other things, probably small things, but bit by bit they build up and he always has an explanation and you don't want to leave him because you love him or you're pretty sure you still love him and what about the children.
N.b. I am not telling you that you should leave him. Your marriage, your husband, only you know what matters to you in a relationship, etc. But. I believe that over the years you have accepted his version of who he is and he has manipulated you to ignore the things that point out that he isn't that person at all. He's not kind and caring and compassionate, because if he was he would know that what he said was totally out of order. Anyone can make a mistake and say something awful, but when they are told how much they have upset someone they don't make excuses for themselves. What's more, you're also making excuses for him, which I'm guessing you've been getting used to over the years.
You may well have lost your friendship. Maybe he wanted you to? I don't know, maybe he's not bright enough to go that far, but he certainly deeply upset someone who is your friend and if you didn't have the courage to stand up for her when he did it, I hope you have the courage to take her side and agree with her now and not make excuses for him.
You need to think about your marriage and who you are within it, in fact you need to think about who you are as an individual and not as a wife who has a husband who tries to make her believe the almost impossible. Were you always like this? Before you got together do you think you had a stronger sense of self, or have you always felt a bit insecure? I know that everything I am saying her is pretty in your face, but I genuinely worry that you are accepting things that people should really not accept. This goes beyond your husband saying something really nasty to your friend, because quite clearly, on some level at least, he is a bully and a manipulator and he has made you believe that this is normal when it isn't at all.