I was on wellbutrin for about a year. It helped with my depressive symptoms a little. (And I mean just a little. I was still pretty depressed, even on wellbutrin). Your pdoc will probably be more apt to try wellbutrin over an SSRI because it is supposedly less likely to cause mania in people with bipolar. However, you already know that it makes you incredibly anxious. You should let your doctor know this. You have other options.

I am on a medication called "symbyax". It is a combination of two different drugs, zyprexa and prozac. Zyprexa is an AP with AD properties; prozac, of course, is an AD. It has really worked for me. So perhaps you could try adding an antipsychotic with AD properties, like zyprexa (or seroquel or abilify). Or, if you are really brave, you could try a really low dose of an SSRI. Be careful with this; SSRIs can cause weird reactions in bipolar patients, and I'm not just talking about mania. Lexapro increased my hallucinations and sui thoughts; I had to quit cold turkey.

Therapy is, of course, a great idea. Having social support is so important for people prone to depression.

Good luck and take care.