my friend need your help...

This is strange and sounds to me like you or your friend is setting up a lot of people to have a broken heart. Yeah you can't help who you fall for in all, but the two of you are married. But, nowadays marriage, monogamy, and honesty don't mean much at all. I just forsee a lot of broken hearts simultaneously breaking as soon as someone reveals that they have fallen for that person they shouldn't be. Your friend says they would never jeopardize the sister in laws marriage, but what about his marriage? What about his wife? And any children if any involved? I think it is a complete disaster that will take a long time to heal from for all hurt parties.

I did a bit of research and my compilation for you is as follows. Infatuation has no age restriction. Infatuation fails to take facts into consideration. It is based on neither reason nor principle. Infatuation sees only what it wants to see or imagines it sees and, being self-centered, is almost invariably doomed to unhappiness. True love is not blind. 1 Corinthians 13:4-7: "Love is long-suffering and kind... does not behave indecently, does not look for its own interests... It does not rejoice over unrighteousness... It bears all things... endures all things." Your friend needs to focus on something other than his own feelings and leave his SIL alone. Flirting with her IS jeopardizing her relationship with her husband. How would he feel if someone, feeling as he does, were flirting with his wife? He doesn't need to tell her anything at all. If he feels so strongly, why doesn't he tell her husband? That way he'll get a truly, honest answer if that's what he's looking for. If he's afraid to tell the husband then he needs to keep his thoughts to himself. References: g98 7/8; g00 6/8; w67 8/1; NWT Bible

So, I am assuming that the husband of this lady is his brother? It doesn't matter. This is family and family should come first. It would be a bad idea for him to follow this idea. If he is wrong about how she feels towards him and she goes back and tells her husband...this will blow up instantly in his face. If he is right and they start an affair....sooner or later it will come out and still blow up in his face. Is he willing to lose a family member or perhaps the entire family for this woman? And lets not forget the trust factor. If she is so easily swayed into cheating on her husband to be with him....she'll cheat on him too. Your friend should stop flirting with her and avoid being alone in the same place with her. We all know this won't happen and where this will go. He does not really really want advice at all. He knows what he wants and knows it is wrong. He is looking for enough people to tell him to go ahead with this plan that in his gut he knows is wrong. Even if everyone tells him not to do it....he probably will go forth.

Being in love with a married person won't do good to you the person you're in loved with. You will be destroying their relationship even if you don't intend to do that. Never bother the person, there are many other women on earth!

I think it is your problem disguised under the pretense of your friend's.Whomsoever it be,it is natural to have some crush like that and it should be avoided as it would cause serious problems within a family.Extramarital affairs may be tickling in the start but let people in great disaster in the course of time.So,it is good to keep some distance and think her as a sister rather than sister in law and respect that relation.Cheers!

It must be stoppped.Forget her and try to love another woman.I know it's hard. if you cotinue,you'll regret someday.God bless you ~

I would say he needs to sit down and tell her what he feels, and ask her to help her get over these feelings, and explain that he does not want to interfere between her and her husband, and ask her to remind him to no longer flirt with them.. If he does want to interfere... Then I suggest counseling or therapy... to help him out... Professionals may have to step in there..... I think he needs to apologise for flirting if he really has a thing for her, as she is already in love with the husband, and it is wrong for him to try to impose his love on her when she already has a love.. but if the husband and her do not have a problem with goofy harmless flirting.. then I would not worry about it.. But he needs to keep his head on and not interfere at all with the relationship she already has.... - DNatureofDTrain

No. I think it must stop, totally. This would be the ultimate betrayal to your friends' brothers. Sometimes we all have crushes on people we naturally CAN'T have, like teachers, & siblings' partners.. That doesn't mean we have to act on them. Personally, I think he should back off - because he knows that's not right. Maybe, ONLY maybe, if your friend's brother breaks up with his wife, should your friend make his move (if he still has feelings for her), but otherwise, NO. He shouldn't act on his feelings, and try to find someone for himself.