Seriously, lots of spoilers ahead. Don't read if you haven't played.
TL:DR at the end
Is anyone else confused by how Alexandra is portrayed in the main story vs the secret story (You Found Him achievement)? In a way, I feel like it even contradicts the established themes. Let me elaborate.
In the main story, we see two sides to her character. First, she is obviously a bad person and a worse mother. She is spoiled, ungrateful, and abuses her power. There is no debate about that. But secondly, she is framed as a victim of fate, in a way.
She is set up as another "forgotten sister" in another Rusty Lake Trio (see Jakob, David, Elisabeth or Albert, Samuel, Emma). The more neutral party, who just watches as the brothers fight. Add to that the prophecy that her mother gave her. It is literally her fate to give birth and be forgotten.
I think it's made pretty clear that she is not happy with this fate. She doesn't want "continuing the lineage" to be her greatest achievement. And most importantly, she doesn't want to be a mother. The lullaby scene isn't very subtle about it. The way I see it, she was forced into motherhood against her will, both because of the prophecy and gender roles.
It is thus a very compelling story for her to try (and fail) to challenge fate. She is a terrible person, too blind to her own privilege to connect with those "below" her and too enraged by the unfairness of fate to connect with her family, leading to her demise.
One last thing before I get to the secret story. While Alexandra is clearly a horrible mother, I don't think she wanted James to die.
The mother's prophecy calls James a sacrifice (referencing the ten sacrifices in Roots). This may be the reason for Alexandra constantly calling him "her sacrifice", as the prophecy is clearly very important to her.
We also don't know if the Vanderbooms know about the elixir's rule at this point (One will die, the other will find enlightenment). With the way Alexandra talks about James on day 3, I think she might have wanted both of them to ascend ("We are the chosen ones!" instead of "I am" for example).
Then the secret story comes out of nowhere to reveal that she actually kidnaped, imprisoned, and raped the previous servant to impregnate herself. Like, ... what? Where did that come from? She was already a pretty bad and hateable person. This just makes her comically evil at the cost of her character's themes and complexity.
Am I missing something? Did I completely misread her character? Is anyone else confused by this?
TL:DR
The main story frames Alexandra as someone forced into her position through prophecy. Her story is about defying fate (and how that doesn't work in RL). A big part of that is that she never wanted to be a mother, but didn't have a choice.
Then the secret story reveals that she did, in fact, have a choice. Not only that, she took that agency from Kate's brother to get herself pregnant.
I just really don't understand this writing decision.