The individual, identified as 28F, recounts a past relationship with a man named Jason (29M) from when she was 20 or 21. The relationship ended when she was 22 after she discovered Jason had cheated on her. More seriously, she found out he had contracted an STD from other partners and knowingly withheld this information from her, despite being advised of the risks this specific STD posed to future fertility.
While the cheating was difficult to move past, the failure to disclose the STD made the betrayal unforgivable, leading the original poster (OP) to feel that anyone in her family should not even be friends with him. After moving on and marrying someone else, the OP’s sister (27F) recently asked for her blessing to date Jason, claiming he had changed, which resulted in the OP completely cutting off contact. The OP is now questioning if her strong reaction and subsequent harshness toward her sister were justified.
AITA for telling my sister she lost me the second she even considered dating my ex who gave me an STD and didn’t tell me?
As renowned relationship expert Dr. Terri Orbuch notes, “Conflict between family members often centers on differing priorities for managing risk and loyalty.”
The OP’s reaction stems from a profound violation of trust centered not just on infidelity, but on a deliberate act that risked her long-term health and reproductive future. For the OP, Jason represents a significant threat that necessitated establishing an absolute boundary: no contact, no acceptance, no association. The sister’s decision to pursue Jason, despite this established history, can be interpreted by the OP as a direct disregard for the OP’s trauma and a prioritization of a new romantic interest over the foundational sibling bond. The sister’s actions place her in direct conflict with the OP’s core emotional safety zone, making the OP’s decision to enforce the boundary immediate and non-negotiable from her perspective.
The sister’s hurt is largely self-inflicted, as she knowingly bypassed a critical emotional barrier set by her sibling. While cutting off contact completely—including ignoring her in public and refusing to speak after an ambush—can be perceived as harsh, it is a powerful demonstration of a firm boundary enforcement when lesser measures failed. A more constructive approach moving forward might involve establishing tiered consequences rather than immediate total exclusion, perhaps allowing a mediated conversation where the sister demonstrates a deeper understanding of the gravity of the original offense before full reconciliation can be considered. However, in this scenario, the OP’s primary responsibility is to her own established sense of safety.
HERE’S HOW REDDIT BLEW UP AFTER HEARING THIS – PEOPLE COULDN’T BELIEVE IT.
The original poster is experiencing a conflict between protecting herself from the pain associated with her ex-partner’s extreme betrayal and maintaining a relationship with her sister, who chose to pursue a relationship with that same individual despite knowing the history. The OP has taken a firm boundary by cutting off contact, which she feels is necessary for her own well-being, even though her sister is now deeply hurt and seeking reconciliation.
Given the severity of the ex-partner’s past actions—which included deliberate concealment of an STD that carried fertility risks—was the OP’s decision to instantly sever ties with her sister the right choice to uphold personal boundaries, or was it an overly harsh response that unfairly punished the sister for dating someone who the OP believes cannot be redeemed?
