PatH I may have used words that were too down trodden however, reviewing the first chapter about Anne - it says she has "an elegance of mind and sweetness of character" the story goes on to say "A few years before, Anne Elliot had been a very pretty girl, but her bloom had vanished early; and even in its height, her father had found little to admire in her, (so totally different were her delicate features and mild dark eyes from his own), there could be nothing in them, now that she was faded and thin, to excite his esteem.
I can see that some of the description is through the eyes of Sir Walter but the message seems to be, her bloom is gone - that I see as her vitality is in her adept mind and character but, not in her appearance that is faded and she is thin. In another era her thinness and adept mind and character would probably hailed her as another Audrey Hepburn however, rather than walking on air as a ballerina similar to Audrey Hepburn it appears with little to no makeup, wearing the fashion of the day that did nothing for someone built with few curves and allowing her smarts to shine instead of a beguiling charm, she comes across as dull and rigid, who suggests ruthless cutting to the bone to get out of debt.
Not that Elizabeth appears very beguiling but then no one is this family seems to nurture a beguiling appearance or disposition. Of all of them Lady Russell seems more the beguiling type and later Captain Wentworth does a fair share of looking and acting the beguiling one.
The best explanation I can find is when Lady Russell suggests Anne was not included in the visits to London and noted she had been discredited by the "selfish arrangements which shut her out,". Arrangements that centered on Elizabeth. Maybe that is the reason Anne lost her bloom.
