Well, when I met my future hubby, we were both JW and you know you are not supposed to marry outside the "religion". At the time we had spiritual compatibility - both born and raised JW's, did not question "mother", it was all we'd ever known.
The problem arises when things change down the road. This can happen with any religion or belief system. If there wasn't a good relationship outside of the "spiritual" component, when that changes there can be problems.
If you love the person for what they are, not what they believe in, I think you can work around the differences.
It's what I'm hoping for in my situation.
BB