What is the light blue pulsating ring around a persons location that changes in size?

When my fiancé checks my location or I check hers, there is a light blue pulsating ring around the contact and it changes in size. What does that ring represent? Because I get accused of being in different places than my location. And when she checks my location when she first clicks on it, it moves me around till it finds me, and she thinks everywhere it moves you when it is trying to locate you our places that you have been?