We see events in our lives through filters like we do when we put on colored sunglasses. If you've been looking through the filter of mental illness for 20+ years it makes sense that reflecting would look and feel different when you are out of that state finally.
It is difficult to get used to meds. They can make you feel blunted and less like yourself. I had a similar experience when I was put on Geodon at 38 after my first episode. I felt like a different person.
However, I found that the core of my being was still there. After some time my body got used to the meds and the aspects of myself I was missing came back, but they were just muted a bit. If you're truly bipolar, muting those extremes a bit is a good thing.
You may find in time you're able to get entirely new perspective that opens up new doors for you. You can obviously look at this new state as a loss, but you can flip it and instead search for the new things you can gain with more stability.
I wish you well and look forward to you posting as you go along.