What Mrs Gould sees is that Charles cares more for the mine than for her; that for all intents and purposes he has left her. Again she refers her own feelings of abandonment to the quasi-widowed Antonia: though her cry is about Antonia's suicide, the "funeral pyre" is her own.
Note that in the metaphor, Charles' death would deprive Mrs Gould of "all
her earthly affections." Of course, one can read this line as meaning only
that she loves Charles exclusively and very much. But it can also mean that
without Charles, her purity of altruism would lose all contact with the earth,
since it is only his materialism that implements it. See "He had given
a vast shape to the vagueness of her unselfish ambitions."