Poorly white grape vine

My 19+ year old vine appears to be dying.  It started growing as usual in the spring but now all the leaves are pale and drooping.  I can't believe that given the weather we are having that it suffering from a shortage of water and the plant has been fed as usual.  Does anyone know what the problem might be.

 and a close-up of the leaves

Too wet conditions will give you the same symptoms as too dry conditions. I would leave the feeding off for now until weather conditions improve.

Thanks, I'll give it a go, don't see I have anything to lose at this point

Check the soil for vine weevil grubs and the leaves for adults and get some nematodes in if you find any.

I can't see any evidence but it might be worth doing in case.  Thanks

As an aside.To my mind, nematodes are a false economy. Being living entities they do not completely wipe out the pest.