I'm so sorry that things haven't shown any improvement for you and you're feeling worse than when you began. That is a terrible place to find yourself after working with someone for four years. Have you talked with your therapist about how things are feeling for you? Is she aware of the fact that your moods continue to plunge downward?

I know how hard it would be to leave someone you've been working with for four years and I don't suggest that, but would you and your therapist consider the possibility of seeking out another therapist for consultation? Sometimes seeing another therapist together is the thing that can stimulate change for both client and therapist. If your therapist works in a peer consultation group or has a supervisor, someone from within this group might be a good person to consult together. I strongly urge you to talk about what's going on with you with your therapist. If you trust her and feel connected to her but can't find your way out of this downward plunge, the two of you really need to find a way to address it. Take care.