My parents were of different religious backgrounds. My father Muslim, my mother Christian, neither are devout and neither imposed either belief system onto me or my siblings. Their relationship didn't last the distance but that had nothing to do with their religion. I personally consider myself spiritual but not religious, but can't imagine 'converting' or having a partners religion imposed on me. I just don't think I would be drawn to someone that wasn't open minded enough to be at peace with my having my own beliefs.