To be very honest with you poster, a practising JW girl will never be happy to be with you in a marriage if you both have different beliefs. She may marry you now out of passion or infatuation but fews years down the line after the heat of passion has cooled off, physical attraction has reduced and stress of life in the world begin to set in, you'll start having problems because she'll start having feelings of emptiness and she'll feel guilty for not sticking with the congregation full time. She'll then open up to her family again and begin taking steps to practise her faith fully then confusing sets in for you as she'll also want your kids to follow her to the Kingdom hall.
Honestly it is a bad idea to marry a witness girl if you dont agree with their beliefs and way of life.

First of all Jehovah's Witnesses are not bothered if you all say that their beliefs are wrong, they try their best to follow the bible principles closely and the examples set by Jesus when he was on earth. so if you say they're wrong for insisting on marrying only people who share their beliefs and way of life then that's just your opinion, and popular opinion isn't always right. Please take note the words of Jesus in Matt. 7:13, 14 ''Go in through the narrow gate; because broad and spacious is the road leading off into destruction, and many are the ones going in through it; whereas narrow is the gate and cramped the road leading off into life, and few are the ones finding it.”

Of a truth, Jehovah's Witnesses are usually happy when most people criticize them in this manner because it makes them experience the fulfilment of Jesus' words during the sermon on the mount. “Happy are you when people reproach you and persecute you and lyingly say every sort of wicked thing against you for my sake. Rejoice and leap for joy, since your reward is great in the heavens.” (Matt. 5:11, 12)