And I think I have figured out exactly what I will ultimately want to say to her most recent statement; that, while we enjoy being extroverted, we can also see the advantages in being introverted to such a high degree, to wanting to be alone, and have in fact enjoyed it ourselves in the past.
Another point that may be key here to figuring out exactly where she's coming from is who exactly is embarrassed. When we talk about ourselves, are we embarrassing ourselves by giving other people information to be used against us, or are we embarrassing others by assuming they care to hear what we have to say about ourselves? Or maybe both? Or maybe another reason entirely? As much as she hates to admit it, she wants to be understood on this issue.
Going to work very soon, but I'll pop on from there.