Hey, if she wants to have sex with him then the worst thing you can do is drive a wedge between you. It's just sex, not love. Be there with here and try to enjoy it as a couple. She'll live you for making her happy.
Since I'm so small she just loves when she with a huge guy..........no I'm not jealous at all I just want her to experience some thing I can't give her....A BIG ONE!
From my view. If my wife was obviously infatuated with a friend of mine for whatever reason I would suggest we discuss it. And knowing her the way I do, we would. The outcome could go different ways. She could leave me which would be ok because relationships don't last forever. Or she could suggest that she alone get naked with him and fuck their brains out just because she at this time needs that experience. That too would be fine. But I'd love to watch or at least a video. Or we could discuss a threesome and do it. Thats fine too. Or she and I could fuck and let him watch and jack off. There are so many different ways this could go.
Wish I could get my wife into a threesome. She's a bit selfish when it comes to the D. I even offered to let her do the MMF threesome but she thinks it's something only singles and pornstars do. She's hardheaded like that!