AITA for making my dad cut off my ex-stepsister?

A young woman’s world was turned upside down when her ex-stepsister, Lily, spun a vicious lie that shattered her family. Years ago, Lily’s false claim that the woman and her stepbrother Max were “dating” led to a divorce, estrangement from her dad, and a ban on seeing Max, her closest confidant. Now, after Lily admitted the truth, the woman demanded her dad cut her off completely to rebuild their bond, and he agreed.

But Lily’s desperate messages—begging for forgiveness or lashing out—have stirred doubts from others, calling the woman cruel. Is she justified in enforcing consequences for a lie that cost her so much, or is she taking it too far? The online community is buzzing with opinions, from fiery support to tough love. Let’s unpack this messy family saga and see who’s in the right.

‘AITA for making my dad cut off my ex-stepsister?’

It all started with a complicated blended family dynamic:

The OP’s bond with Max sparked jealousy from Lily:

The OP cut contact with her dad for years until the truth came out:

The OP demanded her dad cut off Lily, leading to a strong reaction from her:

This woman’s story is a painful example of the long-lasting fallout from jealousy and lies in a family. Lily’s false claim at 14 tore apart the OP’s relationship with her dad and Max, causing significant emotional trauma. The OP’s demand that her dad cut off Lily is an attempt to protect herself from painful memories and set firm boundaries. While it may seem harsh, it stems from a legitimate need to heal and rebuild trust.

From Lily’s perspective, her actions as a teen likely came from insecurity and jealousy in a complex blended family. But her failure to come clean until confronted years later shows a lack of accountability, even as an adult. Family therapist John Gottman notes, “Healing in families requires acknowledging mistakes and making amends” (The Seven Principles for Making Marriage Work). Lily’s silence for years deepened the OP’s and Max’s pain, making the OP’s demand to cut contact a reasonable response.

The online community mostly backs the OP, stressing that Lily must face the consequences of her actions. Some warn, however, that the OP should be cautious with her dad, who once believed Lily over his own daughter. His agreement to cut Lily off is a positive step, but the OP should approach this relationship carefully, perhaps through family therapy to address past trauma.

Moving forward, the OP should prioritize her mental health, consider therapy with her dad to rebuild trust, and maintain boundaries with Lily. Blocking Lily’s messages may help preserve her peace. While cutting contact may seem cruel to some, the OP isn’t obligated to forgive someone who caused such harm without genuine amends. This is a chance for the OP to focus on healing and fostering healthier ties with her dad and Max.

Here’s what Redditors had to say:

The online community came out swinging, mostly supporting the OP and arguing that Lily deserves the consequences of her harmful lie. From empathetic support to sharp sarcasm, their comments light up the debate:

Many backed the OP, stressing that Lily must face the consequences of her actions:

Some criticized the OP’s dad for believing Lily and urged caution:

Some emphasized that Lily has no claim to the OP’s dad:

A few took a humorous or sarcastic jab at Lily’s consequences:

The OP’s demand that her dad cut off Lily came from deep pain after years of trauma caused by her lie. Though Lily seems remorseful now, her failure to confess for years cost the OP her relationship with her dad and Max. This isn’t about revenge—it’s about protecting herself and setting necessary boundaries.

Can the OP rebuild with her dad and Max without the shadow of the past? How should she handle Lily’s persistent messages? Share your thoughts—what would you do in this tangled family drama?