Why is Jonas alienated by his friends after being chosen as the next Receiver of Memory?

Jonas instantly becomes emotionally and intellectually separated from his family and friends. Being involved with the Giver unlocked a world of pain, pleasure and grief that was all new to him. This made Jonas much more insightful than the rest of the town. It's almost like Jonas could see in colour where before he saw in black and white. After Jonas experienced the spectrum of human emotion, he began to have little in common with the one dimensional world of the people he used to know.