Alice Perrers is almost wholly reviled by historians, but many of her "choices" were not hers to make. Think of the time period. What woman could have refused the king and walked away unscathed? A common one, at that.
However, Campion's version of her character was just a tad on the sickeningly naive side for me. Time and time again she was shown through other people, through warnings, through experiences at court that she could trust only a handful, but it was rare that she actually took this to heart. It's frustrating to read about that kind of character.