Hopefully you'll be OK. The volcano appears to be dormant at the moment and although there's no guarantee it won't start up again,things seem to have settled down a bit.
(I was caught up in the middle of things 17th May when my flight to Venice was cancelled at the last minute due to the Volcanic ash.I had to get to the next port Bari to be able to get my cruise & missed the pleasure of sailing out of Venice.)
My advice is to allow at least a couple of days to get there before your cruise. Relax & stop worrying....if I see any news that might affect you I'll let you know.Where do you fly to ? What is the port you sail from ?