First of all, Being a FOB im sure you had the choice to accept or reject this rishta, Knowing full well hes a FOB. Secondly you knew he was your cousin too IMO i cringe at the idea. Anyways The only way you can HIDE it is to just NOT show him to any of your colleagues.
However i feel sorry for him and if i was him i would hide you if you was my wife. That is such a low blow, You cant help hes your cousin you dont have to tell anyone, But seriously? Just because hes a FOB you dont wanan fall into a typical pakistani mould?? Who are you?! Gosh i know English woman showing off their ‘FOB’ husbands And being proud its THEIR husband!!!