One model of suicide is that social alienation and a sense of burdensomeness lead to suicidal ideation, and this, combined with an ability to overcome the fear of death and pain, lead to a suicidal act: http://www.apa.org/science/about/psa...sci-brief.aspx
Obviously there are several models, one involving self-efficacy that would work specifically against types like ITs, which I imagine are the most socially isolated, being the most prone to suicidal ideation.