I think Tarot is what you make of it. You can do a lot of evil with an automobile too, but most people use their cars to do good things like drive to work, run errands, take the kids to the park...
What you invite into it is what you'll get out of it.
When I'm reading for someone I don't know, and therefore don't know what might arise in a reading, I like to say a little prayer, make sure I ground myself and set my intent to obtain helpful information.
I don't specifically ask for protection from evil, but I have never felt that I drew anything in by reading Tarot that was malevolent. I read in order to help myself and others.
If I were afraid of Tarot, on the other hand, maybe bad things would happen. But it's just never scared me that way. Your friend seems to be coming from a place of great fear. Maybe it's not for her, if she has those kinds of fears. I don't think people who are afraid to drive should drive cars either.
You are spirit too, remember, and your spirit has a lot of control of your use of the Tarot.