he's saying that when he's by himself, he doesn't care about other people's opinions of him [["On an island out in the sea, I wouldn't care what they think of me"]]. but when he actually gets around others, everything they think about him and all the judgments they're making gets underneath his skin and kills him [["But in this crowded room I believe that I'm seconds from insanity, Because their eyes just rip me all apart And my temperamental mind decides that I'm being a man"]].
then, everyone gets after him, questioning him about his future and where he's taking his life and if he's going to make anything out of it. this tears him apart because he's not exactly sure himself (and if he even is, the questioning makes him rethink everything he has planned for himself) [["They ask questions about my life//"Where is he going? Who am I?"//And those voices rip me all apart"]]
he's saying that when he's by himself, he doesn't care about other people's opinions of him [["On an island out in the sea, I wouldn't care what they think of me"]]. but when he actually gets around others, everything they think about him and all the judgments they're making gets underneath his skin and kills him [["But in this crowded room I believe that I'm seconds from insanity, Because their eyes just rip me all apart And my temperamental mind decides that I'm being a man"]].
then, everyone gets after him, questioning him about his future and where he's taking his life and if he's going to make anything out of it. this tears him apart because he's not exactly sure himself (and if he even is, the questioning makes him rethink everything he has planned for himself) [["They ask questions about my life//"Where is he going? Who am I?"//And those voices rip me all apart"]]