I picked up The King's Rose after posting an article here, complaining about the representation of Catherine Howard in all the novels I've read. Thanks to Courtney for the recommendation! This novel is exactly what I was looking for.
The King's Rose opens with Catherine preparing to receive King Henry's proposal, and follows her story through to her execution less that two years later.
The first great thing about this novel is how it deals with the spectre of Henry's previous wives. This version of Catherine is pretty naive, readily accepting stories about Anne Boleyn's witchcraft and not thinking critically about the similarities between that and her own situation until it's too late, but this makes perfect sense for a girl who was only 7 when Anne was crowned and 10 when she was executed, someone who shares family with Anne and saw them all turn against her, and someone who's only about 15 and is clearly desperate for approval and acceptance. She wants everything to work out well, so she believes what she needs to believe. Catherine of Aragon was old, Anne Boleyn was wicked, Anne of Cleves was ugly, and Catherine is none of these things, so as long as she doesn't die in childbirth like Jane Seymour, she's going to be fine. The king really loves her, she's doing this for the good of her family, and that's that.
I also loved the way this novel balances the inevitability of Catherine's downfall with her own mistakes and free will. Catherine isn't blameless in her fall, but everything she does makes sense in the moment. She starts off by trusting too much, and once she's begun, she has to keep going to try and stop it falling apart. Although this isn't explicit in the book, one huge element of Catherine's tragedy is how she probably wouldn't have been executed if she had admitted to the marriage pre-contract with Francis Dereham, and The King's Rose really digs into why Catherine thinks that lying about her past will save her, and why it's so deadly.
Everything Catherine does to try and help herself makes the situation worse. She knows she has to live up to the image of queen and keep Henry's approval, so she is extravagant and focusses on her looks. She follows the advice of her relatives, particularly the Duchess, because she believes they want the best for her, not realizing that they're more than happy to throw her to the wolves for the benefit of the family. Becoming queen gets Catherine the family approval she craves, and her desperation for it means she doesn't realize how fragile it is until it's too late. And as she scrambles to maintain her position, doesn't realize the extent of the danger she's falling into, and she becomes more and more entangled as she struggles to handle escalating lies and court intrigues.
If you want a book about a badass protagonist, The King's Rose maybe isn't for you. But it's an emotional and sympathetic book, historically rich without getting bogged down in the setting, with a character tangled up in something she can't understand. A sacrificial lamb from the beginning, but one fighting every step to make things work. That probably doesn't make it hot YA fiction, but it's a really good read. Definitely one of the best books about Henry VIII's court I've read.