Maybe I'm off my rocker, but isn't this exactly what "white lies"[1] were invented for?
You don't actually always have to be 100% truthful with everyone. (That will also serve you badly in other social situations, BTW.)
[1] Point being that even if people eventually find out that you did tell them a "white lie", they'll actually usually be very understanding because that's the societal norm and they realize that you were just trying to "spare them" from embarassment/awkwardness/losing face/whatever.
You don't actually always have to be 100% truthful with everyone. (That will also serve you badly in other social situations, BTW.)
[1] Point being that even if people eventually find out that you did tell them a "white lie", they'll actually usually be very understanding because that's the societal norm and they realize that you were just trying to "spare them" from embarassment/awkwardness/losing face/whatever.