every vote is now worth $$$ to a party for a claim on public funding next election. More than ever, no vote is wasted. That might be an argument for her to research the parties, discover which best reflects her conscience, and vote accordingly.
And yes, this is a very safe Liberal seat. The only question is who will be a distant second place.
One thing I'd say: if she's attracted to the Green Party because of its apparent environmental credentials, this week both the Sierra Club of Canada and Greenpeace gave the NDP's environmental platform higher marks. ("Two Leading Groups Rate NDP Greener Than Greens"
http://www.ctv.ca/servlet/ArticleNews/mini/CTVNews/1087425260777_56?s_name=election2004&no_ads=)