I can relate. I can't really offer answers. But I know how you are feeling. I was diagnosed Bipolar in April. Four different med "cocktails" since then. None make me feel "good". Most make me feel empty. Some do more/better than others. My advice would be to talk to your doc, be honest, and ask about trying something different. I have been told there is no real global "normal" and I just need to find my "normal"; I haven't found it yet, mostly because I have no idea what I am looking for. The other advice I would offer is to look into therapy (if you are not currently in therapy). Therapy can help you figure out your "normal".
Know you are not alone... if that helps.
Good Luck! I truly wish that you find something to fill your empty... something good to feel!