<p>Mental pain is commonly defined as an experience situated on a continuum between cognitive appraisal of the painful event and the affective disposition of the person experiencing it. Drawing on ethnographic material and interviews on severe psychiatric disorders in Bali and Java, I will try to understand what mental pain does to the person experiencing it, as well as to their immediate environment. To answer this question, I will first describe the salient attributes of mental pain as they emerged during my conversations with outpatients and observations of their milieu. These were a challenged “realness” of the experience of mental pain, its ability to take hold of one’s subjective experience, an elusive and relational quality, and a perceived ambiguous and indeterminate temporal dimension. Moreover, I will describe the uncertainties of people navigating a severe psychiatric disorder (health, sanative, social, and behavioral uncertainties), and I will suggest that the salient attributes of mental pain contribute to the makeup of these uncertainties. Finally, this article illustrates that the interrelated nature of mental pain and experienced uncertainties can inform certain illness behaviors, particularly instances of self-isolation.</p>