So the lore for Widowmaker states that she was brainwashed and killed her husband and then Talon kidnapped her again and brainwashed her into becoming the Widowmaker.
My theory is that she wasn’t re-kidnapped. She had served her purpose, she had no value once her husband was dead. She was just a brainwashed ballet dancer and his wife. There is no reason to say, “Hey, just for kicks lets re-kidnap her and brain wash her then modify her into being our best sniper!”
I think she volunteered for it of her own free will. Now that is not to say she killed her husband of her own free will, no she was brainwashed for that, but every choice she made after it was of her own free will.
She wakes up having murdered her husband and the bloody truth sets in, how does one live with that kind of trauma? The deep internal pain of knowing that she had murdered her husband was something she could not live with. She would want to stop feeling what she was feeling so she turned to the only people who could and would be willing to remove her feelings.
She chose to go to Talon and promised them she would do anything if they would remove her feelings and thus Widowmaker was born.
In her personal spawn box talk with Moira the two converse,
Moira, “And how are we feeling Laquoix?”
Widowmaker, “I don’t feel. That’s the point, isn’t it?”
Widowmaker is not perpetually brainwashed, she understands what has been done to her and if she wasn’t there of her own free will she would of turned on Talon the moment she wasn’t brainwashed unless of course in her opinion they ‘fixed’ her by removing her emotions.