Alot of people underestimate the role their height plays when it comes to weight... most women who're 170lbs with their height being between 5'8-5'11 will look good weighing 170lbs but a woman who's around 5'6 & shorter will be fat.
My wife is 5'11 (which is tall for a woman) and weighs 182lbs and she's not fat at all, if you like short women (5'6 & below) which seems to be the case in TLR then a 170 will obviously be too much weight on her.