AITA for Telling My Girlfriend’s Daughter She’s “Not My Kid” and Won’t Pay for Stuff?
I’ve been dating my girlfriend, Mara, for two years. Her daughter Diomara (12) and I have lived together for about nine months. I’ve tried to be there for Dio like a dad—helping with housing, food, school needs, and pretty much everything she needs. Meanwhile her bio‑dad, Dynasis, pops in and out, doesn’t pay child support, and really isn’t involved.
This summer, Dynasis suddenly decides to swoop in and take her for a month. When she came back, she was cold and rude to me. Then she got caught shoplifting at the mall. I picked her up, handled it with the store, and talked to her seriously in a firm voice. She snapped back that I’m not her dad and I shouldn’t tell her what to do. Then when she asked me for money for her sports gear, I told her to ask her real dad. Her mom thinks I’m being immature and not acting like an adult. So AITA for saying I’m not her dad and refusing to pay?
Stepping into someone else’s child’s life isn’t easy. Especially when the “step‑parent” isn’t legally a step‑parent, isn’t married to the mom, and doesn’t have clear boundaries set with both adults and the kid. What we’re seeing here is a clash between emotional roles and financial expectations—a tense intersection of family, identity, and responsibility. And before we decide who’s right or wrong, let’s unpack why this situation feels so raw.
No Legal Dad Doesn’t Always Mean No Emotional Role
You’re not Dio’s legal guardian or adoptive dad. That’s a fact. But emotionally? You’ve been acting like a parent. You’ve paid for housing, food, schooling, clothes, been involved in discipline moments, and even picked her up from a juvenile situation. That’s not just boyfriend stuff—that’s parental investment.
In psychology, emotional investment without formal authority can cause step‑parenting identity confusion (often seen in blended families). Kids may feel torn between two father figures, especially when the biological parent is inconsistent. That inconsistency invites a defense mechanism: pushing away anyone who tries to act like a parent, even if they legitimately care.
So when Dio says, “You’re not my dad,” she’s not just being rebellious. She’s reinforcing her attachment identity—and in her head, she’s clinging to the person her brain thinks is supposed to matter (biological dad), even though he hasn’t shown up emotionally or financially.
This is classic in parent‑child attachment theory.
The Shoplifting Moment: Authority and Respect Collide
You handled that mall situation like an adult. You didn’t yell, you apologized for her actions, you even tipped the guards—the whole nine yards. Then you try to address her behavior firmly but respectfully, and she lashes back: “You’re not my dad, don’t tell me what to do.”
Here’s the reality: kids don’t always respect authority when they don’t perceive it. And in blended family dynamics, authority isn’t just about who’s physically there—it’s about who’s recognized as a caregiver.
You saying “I’m not your dad” in response to her attitude was truthful—but it also inadvertently removed your authority in her eyes.
There’s a body of research on behavior management in teens showing that if teens don’t see adults as figures of consistent authority and attachment, they respond with defiance or emotional shutting down. Her defiance might be rooted in chaos she experienced from her dad’s on‑again/off‑again presence.
Financial Boundaries vs. Parental Expectations
Now let’s talk about money. You’ve paid for the house, her food, her schooling, and more. Meanwhile her biological dad dropped a $100 check once—and it bounced. That’s not just a lack of support, that’s irresponsibility. Yet when Dio comes and asks for money for her sports uniform, she expects you to pay because her dad “doesn’t have it.”
Here’s where the conflict hits financial responsibility of parenting head on. Some people believe that by providing financially, you are a parent. Others believe only biological or legal roles carry that obligation. And there’s no easy universal rule.
But in families where the mom and her partner agree that the partner will support the child financially, that becomes the norm. You stepped into that norm without explicit agreement from both adults first. That’s where parental boundaries should have been set early.
Mara’s Painful Role in All This
Mara is stuck in the middle. She’s angry at Dio for being rude to you, but she’s also defending her daughter’s claim that you’re not her dad. From her perspective, she sees you trying, but also sees the fracture happening between you and her daughter.
This is a co‑parenting conflict. And co‑parenting isn’t just between divorced parents—it happens anytime more than one adult tries to raise a child together. And guess what? Studies show blended and co‑parenting households have higher stress and more conflict unless clear rules are set early.
Mara calling you “not acting like an adult” is her way of saying you didn’t communicate expectations before enforcing them. That’s valid, but it doesn’t erase your emotional and financial contributions.
Why Dio is Pushing Back So Hard
Teen defiance has roots in development. At 12, kids crave autonomy and lash out when they feel controlled. Add unstable attachment with her biological dad, and suddenly any figure trying to guide her feels like an enemy of freedom. That’s not an excuse, but it explains the behavior.
Layer on top:
- She got in trouble (humiliation + fear)
- She had to be picked up by someone she doesn’t respect as a parent
- That person corrected her behavior
- She deflected with “you’re not my dad”
That’s a defense mechanism, not a well‑formed argument.
So Was Saying “I’m Not Your Dad” Wrong?
Not wrong in honesty. But it undermined your role at the worst possible time. It sent the message: you’re not someone I’m invested in raising. That hurts on both sides—emotionally for you, and in her eyes, potentially validating her claim that you haven’t earned the role.
This is the heart of step‑parenting challenges: being present and supportive but not being acknowledged as a parent figure.
Where Things Go From Here
If you want peace and a functional household, consider:
- Setting clear financial boundaries up front.
Explain what you will and will not pay for, separate from emotional support. - Agree with Mara on unified discipline.
Kids follow consistent rules better than unpredictable ones. - Have a calm conversation with Dio about expectations and respect.
Not as a parent, but as someone who cares about her future. - Consider family counseling or mediation.
Blended families often benefit from outside guidance.
As the man’s story went viral, he provided more information on what had been happening
You aren’t an asshole for being honest and setting boundaries—but you are in a situation that needed clearer rules and mutual respect. Saying “I’m not your dad” might’ve felt right, but it deepened the division instead of building a bridge. Real adult action here means creating structure, not just asserting facts.
In the long run, what you do might matter more than what you are—and that’s the toughest part of step‑parenting and emotional labor in a modern family.
So was he TA? Not fully. But this could’ve been handled with clearer expectations and better communication.
