Hamlet doesn't seem to fair very well as a good friend. The only friend he will really trust is Horatio and it seems he asks more of Horatio than Horatio asks of Hamlet. Horatio stands by Hamlet in many scenes. In the first ghost scene, he warns Hamlet not to talk with the ghost. Perhaps if Hamlet had heeded his friend's warning, he would have been a lot happier. Of course, we would have no play---but that's another issue. Horatio helps Hamlet observe Claudius during "The Mousetrap" and when Hamlet re-enters the country from England. The one thing Hamlet does Horatio is to forbid him to commit suicide, but that's so Hamlet's story can be told. As for Rosencrantz and Guidenstern, he quickly ends their friendship and even causes their death when he learns they are reporting to Claudius. And poor Ophelia. Hamlet never tells anyone he loves her until after she's dead. Instead, he makes her suffer because of his self-induced madness and then leave the country after killing her father. In Hamlet's search for the truth, it seems he asks more of his friends than he is willing to give himself.