Masturbation has been condemned in many religions. Even doctors and medical professionals in America once advised against it on 'scientific' grounds, selling devices designed to keep children from masturbating. Did any of them ever have a valid point? Is masturbation in any way wrong or sinful? This hardly seems like a reasonable position; instead, it seems much more like it is based on anti-sex and anti-pleasure doctrines of traditional religion -- especially Christianity.
People can experience a lot of guilt over masturbation, even to the point of not being willing to admit that they do it. That, however, seems to be more a product of cultural problems and not with the act itself. If people weren't continually told that masturbation is bad, then perhaps they also wouldn't feel guilty and depressed when they do it. Maybe if they were told that masturbation is healthy and natural they wouldn't be any more bothered by it than they are by other natural functions of the body.