I have a diagnosis of dysthymia as well. But it sounds like you are in an acute phase of depression and perhaps you require a different drug regimen than what you currently have. Don't be afraid to speak up and demand a new med if you feel the need for one.

By the way, I know what you are talking about in terms of your cat dying. My cat died in August and it was a very major blow for me. Cats can make us feel quite loved and appreciated and it is terrible to lose that support in our lives.