<human>: I am embarrassed about this issue. I really do not know how to deal with this. My husband and I spend time with his brother and wife one to twice per year. Every since they married she has made it a point to be overly friendly with my husband. I have spoken to my husband regarding this and he says she is just friendly. 

What she does: if my husband and I are talking and do not agree she will physically place herself between us and tell him he is right while smiling and laughing up to him. 

This past week we were at his parents doing yard and home repairs. She and I were working on projects outside while husband and brother on other projects. She left me to go assist my husband even though her husband was there to help. I mean every where my husband was for two straight days she was. If he was fixing the sink, she was holding the flashlight, if he was sitting outside fixing the weedeater she was sitting next to him. 

Whole family out to dinner, girls were talking...where was she? next to him. He walked to bar to get a beer she made sure she went to get a drink. I saw red. I couldn't even eat dinner. 

Husband told me he was not doing anything...he wasn't...but I feel she is always trying to build an emotional or mental relationship with him and trying to insert herself into his life.
His brother didn't come sit at my side for two days.

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<bot>: I am baffled. Do sisters-in-law act this way toward bother-in-laws? What should I do? What should anyone do or not do?