I had a similar moment.
My boyfriend at the time and I were heading to the mall. We were about ready to get inside. I'm talking to him, but I wasn't looking at him so I didn't realize he had stopped to tie his shoe for a second and he didn't bother to tell me he had stopped. Meanwhile I'm still walking and talking. Then heard "Are you talking me me?" I looked over and realized my boyfriend was not at my side, but there was a woman three feet away from me on the same side who was walking inside, too. I looked around and found my boyfriend a few feet behind me tying his shoe. I was embarrested! I apoligized to her and explained I was talking to him and didn't realize he had stopped.