When there is a Mother below, there is no Daughter beside, and Mother beside mourns her.
People move on with their lives.
They don't forget--of course they don't forget--but the things that consumed their lives take up smaller pieces. We are born to survive, and though that is true of creatures bound by more traditional rules of evolution, it is particularly true of those who are immortal.
Immortals are not known for reproducing regularly. They live, individually and eternally, or they do not exist.
The seasons follow Mother beside's moods. She does not always force this, though she can. Often, it is simply the natural way of things. Often, none but Mother beside could say whether the moods follow her weather, or the weather her moods.
When her daughter is away, she mourns, for she knows her daughter's hurt, and for this is the closest thing to death that Daughter beside is likely to experience.
Yet, still. People move on with their lives. Mother beside is no different in that.
There is winter, and there is snowfall, and these reflect her moods. The weather reflects her emotions. The gods give us names for many things, and concepts for more. Though the word is not named after her, there is a word for Mother beside's happiness in the midst of her mourning.