I think fear of starting all over (or perhaps not so much fear but a sense of the enormity of the task) was part of what kept me from trying a different therapist when therapist #3 clearly was more counterproductive than helpful, and that I made a big mistake by staying with her for as long as I did (and repeated the same mistake with #4). But everyone is different. It is a decision we each have to make for ourselves. Regrettably, we can't know in advance if we're making the right decision, and we have to live with the consequences if we make the wrong decision. I wonder if your therapist could make some suggestions of therapists she thinks might be better for you, and you could try them, but come back to your current T if they don't work out? Although, that might not work out financially if you are using insurance.
Another possibility is to see if your T would be willing to try alliance and outcome evaluations. I think there are some available on the web at links from http://www.talkingcure.com/.

I don't think I've ever felt comfortable with a therapist. I went into therapy assuming I wouldn't feel comfortable, since I couldn't imagine feeling comfortable with one. But the problems I encountered were more than just feeling comfortable.