For years she blamed it on drugs, then in middle-age she switched to bipolar illness. Nevertheless, she did managed to do a respectable, if not spectacular, amount of work over the years.
Her advantage in Star Wars is that she didn’t LOOK nineteen.
I don’t know what substantial work she ever did as an actress. I just don’t think Lady Lei or whatever the hell she played in that movie was up there with Long Day’s Journey into Night. She wasn’t pretty then (her poor body was obviously tortured into that sculptured look during the 1970s) and she’s a bit of a disaster now.
I’ve also have problems with people in L.A. telling me that she’s a great wit (if not a great actress). The evidence of that is she wrote an off-Broadway show called “Wishful Drinking.” Yup. Right up there with Oscar Wilde, lol!