Valley Girl--
I had a somewhat similar experience, having quit the piano for about 10 years. And about a year ago I decided to take it up again. I have a long track record over a long life of playing the piano.
When I took it up again, I decided I wanted to play show tunes. I purchased a couple of music books of "themes from the moves," popular hits, and the like.
That lasted a couple of months, but somehow these were not too satisfying. Without consciously intending to do so, I went back to classical piano music.
It must have taken me about 10 months, but I believe I'm as good now as I have ever been. I am really not that skillful -- perhaps late intermediate, or about grade 8.
One change in me -- I have developed a distaste for the over-played, tired old chesnuts that everyone seems to play. They are great music, don't get me wrong. But I just can't look at them anymore. Perhaps because I am so old, and over my long life I have played these tiresome things again and again. Fur Elise, Moonlight Sonata, the easy Chopin waltzes, Spinning Song, and on and on. Of course, when I was young, these were all new to me! (Those were the days.)
My latest thing of these past few months is to find composers or compositions that I have not experienced before. Almost everything I play now I have never heard played. So I have to explore them by reading sheet music. This is partly because these composers are minor composers and rarely recorded. Or if recordings exist, they are rather obscure and hard to find. This adds a sense of adventure for me.
Oh, and I have a teacher and take lessons. She "keeps me honest!"
Hope you enjoy your return to the piano!
Topic: Re learning as an adult.