my current fiance is an unbelieving mate and I am willing to make any sacrifice for her
You wanna bet? If you are married to your wife, you have entered a binding agreement (you will suffer sanctions if you break the agreement) with her. As a baptized jw you are also in a binding agreement (you will be disfellowshipped and shunned if you break your agreement) with another group of people
So if it comes down to pleasing your wife or pleasing the org who is going to win. She is just an unbelieving mate. They are (you believe) Gods organization. To oppose God's organization is to oppose God! She will always be second fiddle.
Your fiance should tread very carefully. Especially if she wants her children to be able to think for themselves free from mind control methods that would make any chi-com commander of a pow camp proud.