The right thing to do is to thank them for their work, let people know that they're moving on, and. . . you don't really have to explain all their personal details. It's more important to leave them with their dignity. . . and let them go on to live another day. Remember, what you say at that meeting, that's their reputation.
I was with Brian De Palma at the time, and he said he wrote the role specifically for me. I don't know what that says about the way he saw me, since the role was of a castrating killer. Brian came one morning to the house, said "Here's your Christmas present. " He wrote the character to have a Swedish accent, but since I couldn't pull that off, he switched it to French-Canadian. It was such a romantic time in my life. Everyone was young and passionate and convinced they were going to change film forever.