Over the last 25+ years OH and I have put on a certain amount of weight (!) and not surprisingly our respective wedding rings have become tighter and unable to get them off. Fed up with feelng that horrible tight feeling around my finger, I poured a load of olive oil on my ring finger and the ring eventually came off. I then had my wedding ring (and engagement ring) made slightly larger and it's fine now. However, I lost my appetite about 7 weeks ago and have lost a little bit of weight - so my wedding is a bit loose, as is the ring I wear on my left little finger. OH said his ring was feeling a bit tight and I eventually managed to persuade him to go to our local independent jeweller, where they eased it off and, once his finger has gone back to normal, he'll get it enlarged.
I also think you should try one of those little things you can slip on to the ring to take up a bit of room ....