Steve | Tony
Maybe since a lot of it might be to do with the biology thing, it would help for her to talk to another woman? Maybe one who has been through it? I know there are people here who its happened to like that.
But otherwise, I'd say being patient and sticking around for when she might need you, sort of letting her know you're around too.
Or, hmm, what's something small we could do that would make her happy in a little way? Sometimes even something like someone having your favorite ice cream in the freezer helps.