Have you ever been in a situation when your husband's friends start making comments or advances or passes towards you. I don't know if this happens to anyone else, or if its happened or happens to anyone either!

This is something quite common which happens to me, but please don't take it the wrong way, as I don't flaunt any of my parts and give the initiative to others. But i do speak whats on my mind and am open in what I think about the the topic they are talking about with male friends of course when my husband is around with me.

When such situations do occur, I don't say anything there and then, instead come home with my hubby and tell him, so nothing is hidden from him. I believe its good to be honest and therefore only share these things with him.
I have to admit its good to be flirted with although it does get very uncomfortable, when it comes to sexual advances that's over bored and crossing the limits.
Our male friends also being to confide in me, and share their secrets with me, such as them having affairs, all this does stay with me, as I don't want anyone's marriage to break and only tell my husband. I don't make any comments to what they say, just simply listen if they start talking or do try to change the subject.

Is this a way for them to say that they go outside their marriage and trying to tell me that it can happen as in advertising it?

Does the situation going on here?

I think your actions of being honest with your husband is the best way to react. With the people who have been making advances towards you, you should make it clear that you are a happily married woman, and you don't appreciate their advances. If their advances make you uncomfortable, tell them that and kindly ask them to stop. You have to be careful about these things. When men are turned down, they can become aggressive.