Board Thread:Questions and Answers/@comment-30049122-20160923233523/@comment-11856834-20160924002346

Except you have to take the Ise curse into account. If she already had one husband die when men who marry into the family tend to die, why would she risk subjecting another unknown man to it?

And as for the issues of age and time, you have to also take into account that aging for Shinigami throughout the series has been inconsistent, so that really isn't a useful gauge for something like this.