The #MeToo movement has brought greater visibility to the topic of sexual assault in public discourse. We analyzed a dataset of 1,070 Twitter #MeToo self-disclosures to examine the relationship between online visibility (retweets and favorites) and the content of victim-survivors' self-disclosures such as victim's gender, relationship to the perpetrator, and the emotions expressed in the tweet. The visibility of sexual assault self-disclosures was shaped by the extent to which they align with stereotypical misconceptions of victimization. These findings carry significant implications for understanding patterns of victimization, and for identifying whose voices are being amplified or not on Twitter.