Have you ever been really great at something, anything? I don’t mean ok, or better than average, I mean really good. It’s a great feeling. Every bit of practice, all the blood and sweat that went into getting that good, is worth it in the end. You feel vindicated by having a new skill.
Have you then, for whatever reason, stopped doing this thing you were great at (notice the past tense there, it’s lucidly foreboding)? You just haven’t done it in a few years. Maybe you were bored with it, had other commitments, or a vital piece of equipment was no longer available. These things happen, and moving on is the right thing to do.
So, after your “away” spell, you come back to your skill because the situation is now like it was when you started it; your stars in alignment, your interest peaked, whatever. And then the inevitable part: you can’t do it anymore. The years of practice forgotton, the sweat gone, and the clumsiness aparrent for all to see.
It’s depressing, and embarassing. You know you could do it, you have evidence to prove it, but you can’t do it now. In time, you could get it back. But after the initial shock, do you really want to go back through the rigour of training again? That’s up to you, and I can offer no advice either way.