I always remember we are all human beings. I handle it as I would handle every relationship. Some people I know better than others. A provider I knew like family I would even go up to and say hello. Other people I would acknowledge and at least smile. I guess I do not understand why you would feel uncomfortable unless you think that the provider is going to blurt out exactly how you know each other. There are just too many easy lies that you can use, e.g., met at a party, goes to my gym.