Guitars will get many dings and nicks over the years if they are played... A wedding ring isn't going to cause any significant damage from regular play. And that would also depend on your practices as a guitar player... if you are rubbing and mauling/drooling over your guitars... lol Then yes you may add an occassional stratch to the guitar from your ring..
You may want to remove it for any guitar lovemaking.. :p
Great works are performed, not by strength, but by perseverance.