You have no control over who your fiancee will find attractive and want to be with, so I think any rules about what kind of person she is "allowed" to start a relationship with are rather useless. And more than a bit dictator-ish. How about you forget rules and try trusting that your fiancee, a grown-up who loves and cares about you, has enough brains to choose well and enough consideration towards you to treat you respectfully and kindly? People in adult relationships don't actually need rules, and making up rules for someone to follow sends them the message that you don't trust their judgment.
