Give that a little thought. Polyethylene is what's used for vapour barrier in the walls of most buildings. They wouldn't use it for vapour barrier if it was as poor a barrier to moisture as you suggest. I expect what the problem is is that every time you open the bottle, you fill the container with more warm humid air and the glue gradually hardens up in small steps until it becomes unuseable.

I don't know whether Gorilla Glue is a moisture cure polyurethane or not, but if it is, then the trick to storing it for long periods is to put it in a place with negligible moisture content, and that means your fridge's freezer (best) or upside down in a container of motor oil. I've stored PL Premium both ways, and both ways work, but the freezer works best.

LePage's PL Premium is a moisture cure construction adhesive, and I keep it in my freezer between projects where I need it. I just "candy cane" it by squeezing a little bit of it out and immediately put it in the freezer. I only squeeze out enough that I can grip reasonably well.

The low temperature in the freezer both ensures minimal humidity levels in the air and minimal chemical activity so that whatever humidity there is in the freezer air doesn't react with the construction adhesive. The result is that the stuff will keep for a very long time under these conditions. The part that got squeezed out when I candy caned it will become hard because of the moisture it absorbed when squeezed out. But, I just put the cold tube in my caulking gun, apply pressure to the glue and pull the candy cane out, and the new glue will start to slowly come oozing out. Let it warm up, and it's ready to use again. I've stored PL Premium for well over a year in my freezer, using it periodically as needed, and it's still good to use now.

I expect the Gorilla Glue, if it's a moisture cure polyurethane glue could be stored equally well in a freezer.

I've also cut the top off an old milk jug and filled it about an inch full of motor oil. Candy cane a bit of PL Premium out of the tube and immediately put it upside down in the oil. The glue at the tip of the tube can't cure because there's negligible H2O content in the motor oil, and that prevents the glue from curing even at room temperature.

It's just a matter of understanding that the glue requires moisture to cure, and recognizing those places where moisture is all but completely absent.