Miriam's Lovers Age Not Because of Some Inevitable Natural Process, But Because She Loses Interest In Them.
When Miriam takes on a new lover, she bonds with them and her youth and powers extend to them only as long as she feels deep affection for them. If she falls out of love with them, even subconsciously, then they start to age. Miriam's "Love Attention Span" may extend no longer than 300 years or so before she starts to get a wandering eye and begins looking for a replacement. Once that happens, her present lover starts to decay.- If this is true, then perhaps the reason none fully die and become dust when she loses interest is on some level she still loves them. Her love for them keeps them from finally dying.
