  Understanding the cognitive and emotional perceptions of people who commit
suicide is one of the most sensitive scientific challenges. There are
circumstances where people feel the need to leave something written, an
artifact where they express themselves, registering their last words and
feelings. These suicide notes are of utmost importance for better understanding
the psychology of suicidal ideation. This work gives structure to the
linguistic content of suicide notes, revealing interconnections between
cognitive and emotional states of people who committed suicide. We build upon
cognitive network science, psycholinguistics and semantic frame theory to
introduce a network representation of the mindset expressed in suicide notes.
Our cognitive network representation enables the quantitative analysis of the
language in suicide notes through structural balance theory, semantic
prominence and emotional profiling. Our results indicate that the emotional
syntax connecting positively- and negatively-valenced terms gives rise to a
degree of structural balance that is significantly higher than null models
where the affective structure was randomized. We show that suicide notes are
affectively compartmentalized such that positive concepts tend to cluster
together and dominate the overall network structure. A key positive concept is
"love", which integrates information relating the self to others in ways that
are semantically prominent across suicide notes. The emotions populating the
semantic frame of "love" combine joy and trust with anticipation and sadness,
which connects with psychological theories about meaning-making and narrative
psychology. Our results open new ways for understanding the structure of
genuine suicide notes informing future research for suicide prevention.
