Based on the given sentences above, the one that is punctuated correctly is the second sentence: She sends an email therefore, to her instructor and advisor. What makes the first sentence incorrect is that, it has no period at the end of the sentence. Hope this answer helps.
I would think that "insensitive" meant that his other girlfriends thought he didn't care, or he was a total idiot or soemthing. Just something like that. I hope this helped a little bit love!
