Please try to contact your pdoc or seek a new one, there are alternative meds that can help you.
Lithium is a great drug, but if you are more inclined to the depressive end vs the manic end, you may require an AD in adjunct or switch to different med.
But don't be consumed by the depression, there is help to get out of it or minimize it.
In my case, Lamictal was what I changed to, I am BP-II also and had been misdiagnosed as having clinical depression, so for a few yrs I was not getting proper treatment, which I partly blame seeing a GP vs a PDoc, GP's are not qualified to substitute for a Psychiatrist.
Try not to put off seeking professional help, things can work out. I've been there, and can relate to your post, as well as many who come to this forum.
Please take care,
DE