Welcome to Just answer !
Well, these drugs which you are taking currently , are the mainstay of treatment for Bipolar disorder , so i would not suggest to change these drugs , as one should never change something that has worked for you all this while , and you also need to understand that these drugs take some time to act before they get you back to 100 percent previous self , but having said that we can definitely add a thing or two in your current regime.
So, i suggest that you may start yourself on Psychotherapy ( counseling) , this would definitely help you in recovering from your depressive state and will speed up the process as well. The best psychotherapy for depression is Cognitive behavioural therapy ( CBT) , and it is a short course therapy which is given by a clinical psychologist or psychiatrist .
Along with this , you may ask your doctor to start you on anti anxiety drug such as either Clonazepam ( klonopin) or Buspirone ( buspar) , as these anxiolytics/anti anxiety agents act as good adjuvants to mood stabilizer such as lithium and anti depressants and speed up the process of recovery , but , besides all this i also would advice you to keep your patience intact .
So, i sugegst you start on the above mentioned two modalities of treatment while continuing your present treatment , and i am quite sure this will help you to get your desired response and speed up the process of recovery.
I wish you rapid recovery to best of health.
I hope my answer serves your query according to your satisfaction.