Liz - I am about the same age as your friend, I am 53, and had my ND almost 2years ago. EVERYONE tells me how they cannot even tell or see the scar. My doctors did the incision from the midpoint of my chin, right underneath my jaw, back to below my left ear and then they brought it straight down so that it wouldn't be as noticeable. (My hair covers the part under my ear) I have actually joked with my surgeon that he should have done the other side too as it was almost like a mini neck lift! Less wrinkles on that side! (not that I am that wrinkled yet anyway!)
As far as physical symptons, I do have some tightness on that side of my neck, numbness as well esp. my ear and side of scalp, but I really don't think about it much. When I first had it done, it was a little scary as I could not lift my left arm out to the side and then raise it all the way up, and had a droopy lip, but both resolved quickly. I did my physical therapy exercises religously and still do them when I think about it...