Either calls off wedding...return it
Guy cheats on her with her best friend months before the wedding...pawn that ring!!
Husband cheats on her during the marriage....pawn that ring!
Why would her name be on the title if he had it before they were together?
Women never cheat. at least put that scenario in there.
If the wedding is called off, then I believe she is required to return the ring as the ring was part or sign of a "contract" or "agreement" to get married. If no marriage, the contract is void. Divorce is different because the contract/agreement has been fulfilled once they said "I do." Therefore, she keeps the ring. However, I'm not an attorney so someone else may be able to verify or disprove my statement. But I have been through both scenarios with said results.