Being that you still have your gown ... I'd encourage you to keep it in tact and show it at your anniversary celebrations. Or perhaps throughout the year during get togethers with family and friends. This may be as simple as one person dropping by for tea. Many will enjoy seeing it and will help you enjoy your significant milestone all the more.
Now here's the twist ... Being that you are interested in using it for a quilt., start planning your quilt!! Of course, the design and start looking for fabrics to mix with it, etc. Your design might include some photos from your wedding day, dates, etc. And .... have all those who "see" your dress and help you celebrate, sign signature blocks with their wishes to you.
Then after it's all over .... if you are wanting to cut up your dress, go for it and have a fun time putting it all together.