it's not about whether he is having an affair or not. Let's assume (which is most likely) he is NOT having affair. Does it make you feel more comfortable with their 'friendly' outings till late night? I don't think so.
I understand, like in my case, my hub is younger than me, and we agreed that even though we do have our common friends and we do go out together, he will still have rights to go out with his friends only, as well as I have rights to go out with my friends only.
To be honest, it still bothers me, but at least I understand the nature of this issue, and accept it, knowing that he is faithful to me. By the way, I know all his friends who he is going out with (among them there are some pretty girls as well), sometimes they come over to our place, and some of them I have on FB as friends.
But another concern is that it might eventually lead to disunion and separation, when he is starting having his own circle without involving you in it.
Men like freedom, nothing can help... Not necessarily having affairs... They always feel that they are missing something in life... And it's up to you to act wise and carefully and do not push him away by your constant "talks", complaints and tears..
Some men just getting angry when they see their wives constantly crying and complaining..
But to be honest, in general it is not a good sign... not good at all...
Many suggest you to “sit” him, to “question” him, to “investigate” the case, and so on.. be very careful.. it only might push him away.. All these things like “ I am your wife! I have rights!” are good if you are ready to go all-in, and ready to lose him.. because you might hear in return something like: “Fine! So if you put question this way, you won’t be my wife anymore!”.. So again, be very delicate , chose your words and actions very carefully..
Uff, good luck on it!


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"What lies behind us and what lies before us are small compared to what lies within us."
Oliver Wendell Holmes