From the URL that Orange posted -- see the text in bold for a connection to what people say on dpselfhelp.com:
Hunter, E.C., Baker, D., Phillips, M., Sierra, M., & David, A.S., (2005 in press) Cognitive Behaviour Therapy for Depersonalisation Disorder: An Open Study. Behaviour Research and Therapy.
Depersonalisation (DP) and Derealisation (DR) are subjective experiences of
unreality in, respectively, one's sense of self and the outside world.
These experiences occur on a continuum from transient episodes that are frequently reported in healthy individuals to a chronic psychiatric disorder that causes considerable distress (Depersonalisation Disorder: DPD). Despite the relatively high rates of reporting these symptoms, little research has been conducted into psychological treatments for this disorder. We report on an open study where 21 patients with DPD were treated individually with Cognitive Behavioural Therapy (CBT).
The therapy involved helping the patients re-interpret their symptoms in a non-threatening way as well as reducing avoidances, safety behaviors and symptom monitoring.