Is simple, take an invidious child and she will say lies about you from all your friends.

Is happened this, a people (her name is "H") decides one day to do bad things about another people (his name is "D").
H talk talk and talk about D to other, but she says lies because other peoples (names "A" and "R") are friends for D. D when is back at home understand all and try to contact R, but she doesn't want to talk with his and she blocked in msn. Then D tries to contact her in one website (named "L"). But A kills and permbans him from the chat. D tries to send a pm on the forum, but A was quickly, so she banned D also from forum.
D now doesn't know how to do for save his friendships from A and R.
What D can do?