Marriage is largely ruled by the law of contracts.
Although, in this case he may be in breach!
well, since he is in jail, he can’t come get it so she ought to keep it,,for her trouble and inconvenience. Just finding the girls underwear in his appt is trauma enough for her to keep the ring not to mention the murders.
How could a woman know a man and be engaged to him and not know he was seriously antisocial.