For whatever reason my original post on this has gotten a lot of traffic which has led me to think more deeply about this subject.
One thing I have heard in my Christian experience is that outward symbols reflect an inner reality. For example, kneeling in prayer signifies humility before God, and baptism symbolizes our spiritual death, burial and resurrection.
So to me the wedding ring symbolizes unbroken love. An additional idea is that the circle represents eternal love, which goes along with our promise to love until death. Rings are usually made of gold or silver which are precious metals and symbolize the preciousness of our love and commitment.
During our separation just looking at my ring reminded me of the commitment I had made to love my wife. I think it also helped me recall our wedding day.
If you are separated spend some time asking yourself what it meant to you when you received it and what it means to you now.