AITA for hiding this from my gf?

A 27-year-old guy dating a 31-year-old woman with a 15-year-old daughter suddenly found himself in a tough spot. The teen opened up to him about having a girlfriend her age and begged him to keep it quiet, worried about how her mom would take it.

Her mom got pregnant at 15 and went through serious trauma back then, making her fiercely protective and dead set against teens dating—boy or girl, it wouldn’t matter. Now he’s torn between honoring the kid’s trust and worrying that hiding it longer could hurt his relationship with his girlfriend and the bond between mother and daughter.

‘AITA for hiding this from my gf?’

The whole thing started with the daughter’s unexpected confession:

He’s caught between trust and honesty:

The edit adds crucial background about the mom’s past:

The core issue revolves around a teenager’s privacy and emotional safety as she explores her identity and feelings. When a 15-year-old chooses to confide in a non-parent adult, it signals deep trust—breaking that could cause lasting damage.

While the mom’s concerns stem from genuine past pain and fears about teen dating, blanket opposition might push her daughter toward secrecy instead of open communication. Research from the American Psychological Association shows family acceptance is the biggest protective factor for LGBTQ+ teens’ mental health, dramatically lowering risks of depression and self-harm.

Relationship expert Brené Brown stresses that trust builds through small kept promises, and one betrayal can undo years of effort. Outing the teen without cause could shatter her faith in adults and hinder future help-seeking.

The healthiest path is gently encouraging her to share when ready, while subtly preparing the mom through general talks about growth, trust, and acceptance. Only intervene if the relationship shows red flags—for now, silence paired with support feels like the most compassionate choice.

Here’s the input from the Reddit crowd:

Pretty much everyone online agreed he shouldn’t spill the secret, stressing how fragile trust is with a teen figuring things out.

Some suggested ways to help long-term instead of just staying silent:

Plenty hammered home never outing someone on your own:

Others weighed in on teen dating in general:

The online crowd overwhelmingly backed keeping the teen’s confidence, warning that once trust breaks with a kid navigating big feelings, it’s incredibly hard to rebuild. Gently nudging her to open up when she’s ready came up as the smartest move.

So where exactly is the line between being honest with your partner and safeguarding a child’s privacy? Could keeping a secret like this ever become too heavy to carry alone? What would you do if you were in his shoes?