Archbishop Vincent Nichols said MySpace and Facebook led young people to seek what he termed short-lived friendships, with quantity becoming more important than quality.
He said a key factor in suicide among young people was the trauma caused when such loose relationships collapsed.
Archbishop Nichols said society was losing some of its ability to build communities through inter-personal communication, as the result of excessive use of texts and e-mails rather than face-to-face meetings or telephone conversations.
