OP you gotta remember that we are wounded with original sin. Fulfillment in its fullest sense is only going to happen if we make it to heaven. While we are here, we retain our human condition, and this means that even the holiest of us here are not fulfilled. Remember the verse about the clay and the potter? You’re still in progress, so don’t expect to be completely fulfilled here. This isn’t prime theological advice I know; all I’m saying is match your expectations with reality and understand that we are the clay, and we are still being fashioned.
I highly recommend spending more time doing all Christian activities, like that of scripture and prayer. I’ve also heard Dark Night of the Soul is a great read and I need to read it myself, I usually see it mentioned concerning questions like these.