With Ryan Condall's fanfiction coming out soon, I just wanted to point out that no matter how the ending of HOTD is changed, Aegon III falling in love with and marrying Daenaera Velaryon is canon. No "fixing" in any adaptation will change that.
In the book, Jaehaera loved Aegon, but he didn't care about her, didn't even share a room with her. So don't come here with all the "Romeo and Juliet" or "potential" bullshit because it's a one-side-attraction from Jaehaera.
To those who say Jaehaera was suited for Aegon, she couldn't do anything but cried and locked herself in the room. And you think marrying Aegon was good for them both? She had no family left, even her servants hated her. Lady Cassandra Baratheon is even suspected for murder her because of resentment and jealousy.
....she found herself of little account in King’s Landing, and bitterly resented having to care for the weepy, feeble-witted child queen whom she blamed for all her woes
One of the queen’s bedmaids also came under suspicion, when it was found that she had stolen two of Jaehaera’s dolls and a pearl necklace. A serving boy who had spilled soup on the little queen the year before, and been beaten for it, was accused.
People even suspected that Aegon commanded the guard to murdered her himself. She is the daughter of the man who killed his mother after all.
“It was the
king,” whispered still others. “She loved him with all her heart, yet he
paid her no mind, showed her no affection, did not even share his
rooms with her.”
"It would have
been a simple thing for him to slip inside and throw the child from her
window. If so, surely the king himself had given the command. Aegon
had tired of her weeping and wailing and wanted a new wife, men said.
Or perhaps he wished to revenge himself on the daughter of the king
who killed his mother. The boy was dour and gloomy, no one truly
knew his nature."
But in the end it's all a theory, none of it confirmed either her death is suicide or murder.
The true tale of
how Jaehaera Targaryen met her end will never be known. Mayhaps
she did take her own life in some fit of childish despair.
After Jaehaera's death, the Council urged Aegon to remarry and arranged many noble ladies for him. Aegon had no interest in any of them, but he felt more comfortable with Lady Myrielle than he did with Jaehaera. He even gifted her Jaehaera's doll.
Mushroom
tells us that King Aegon said little as they ate, but “seemed more
comfortable with Lady Turnips than he had ever been with Queen
Jaehaera. Which is to say, not comfortable at all, but he did not seem
to find her presence distasteful. Three days before the ball, he gave her
one of the little queen’s dolls. ‘Here,’ he said as he thrust it at her, ‘you
can have this.’
"When His Grace greeted Lady
Myrielle by name and said not only, “It was good of you to come, my
lady,” but also, “I am pleased you like the doll”
Also, Daenaera and Aegon III marriage IS NOT A MARRIAGE OF CONVENIENCE. Aegon truly fond of her at first sight and quickly put and end to any attempt to try to break them up.
Daenaera’s smile transformed her
face, men agreed; it was sweet and bold and mischievious, all at once.
Daenaera represents hope and a new beginning. She has personality and is the one who puts an end to the dark times of civil war. In contrast to Jaehaera, who symbolizes the remnants of the enemy.
"Those who saw it could not fail to think, “Here is a bright, sweet,
happy little girl, the perfect antidote to the young king’s gloom.”
When Aegon III returned her smile and said, “Thank you for
coming, my lady, you look very pretty,” even Lord Unwin Peake surely
must have known that the game was lost."
King Aegon III Targaryen wed Lady Daenaera on the last day of the
133rd year since Aegon’s Conquest.
Aegon III and Daenaera are always end game, no matter what they are trying to change or fix in the live-action adaptation. You can make up your own headcanons, but don't twist what GRRM wrote and shoving "This is better!" Or "But they are canon in the series!". The book and the series are entirely different from each other.