my wife is Moroccan she comes from a Muslim family, she is in NO WAY religious and never has been but her family is VERY religious. Her brothers wife studied Islam in college and she will be the first to tell u that ISIS and other extremist groups DO NOT represent Islam in any way shape or form.
While ISIS may not represent the kind of Islam with which your wife is familiar, it most certainly represents Islam. It's ridiculous to suggest that it doesn't.
Also, assuming you are not a Muslim yourself, it is forbidden in Islam for a Muslim woman to marry a kaffir.