In the age of social media, public perception of borderline personality disorder (BPD) is shaped as much by clinical settings as by online comments. This study aimed to explore how internet users react to TikTok videos about BPD. The primary objective was to identify emerging themes in the comments and to better understand social perceptions of BPD in the digital space.

A qualitative study was conducted, based on the systematic collection of 25,197 comments from 141 public TikTok videos about BPD. A representative sample of comments was extracted and subjected to thematic analysis using a categorical iteration method. Themes and sub-themes were identified inductively, based on rigorous coding and cross-validation among evaluators.

The results reveal a strong concern among internet users regarding diagnostic confusion between BPD and other psychiatric disorders, particularly autism spectrum disorder and ADHD. The issue of self-diagnosis and self-treatment is frequently addressed, reflecting a need for identity appropriation and mistrust of professional diagnoses. The impact of BPD on interpersonal relationships is widely discussed, ranging from relationship tensions to coping strategies. The ambivalent role of social media is highlighted, both as a source of support and a vehicle for misinformation. Finally, internet users report experiences of social isolation, stigmatisation and fear of being labelled, emphasising the importance of emotional support in the recovery process.

TikTok is becoming a space for building mental health identities for people living with BPD. Our findings call for the development of digital education initiatives and targeted interventions to counter stigma and support care pathways in the digital environment.