Was she being dismissive or attempting to offer some comfort?
If she was dismissing your concerns, I would suggest trying to communicate your distress over these occurrences. If she remains unsympathetic, I would think about finding a different therapist, and not bother trying to convince her.
The voices, IMO, are no more dangerous than thoughts that come unbidden, but they are a great nuisance. I've had them; it's as if there is some small person sitting on my shoulder, just behind my left ear, spitting out nasty sound bites. Fortunately, I had a psychiatrist who was sympathetic. He prescribed low doses of Risperdal and the problem went away. The next psychiatrist stopped the drug, but restarted it after about a month, when the nasty little man came back.
As I understand it, statements such as the ones that you hear from your "voice" may reflect psychological problems that should be dealt with. Here are some links that you might want to consider:
http://www.mentalhealth.org.uk/page.cfm?pagecode=PMAMHVhttp://www.mentalhealth.org.uk/profilenews.cfm?areacode=mh_hearing_voices_news&pagecode=PMAMHVLN&print=1http://www.enotalone.com/article/3109.htmlhttp://en.wikipedia.org/wiki/Hearing_Voices_Movementhttp://www.psychologyinfo.com/schizophrenia/There is much more information on the Internet.
IME, the voices themselves are harmless, but they could drive a person nuts. :)
On edit: removed link to an author who apparently confuses "psychological" with "psychic".