Or maybe, it's about someone who doesn't have the nerve to tell he's in love with this girl (or guy). He fantasises about how it would be if he would have the nerve to say it (And maybe someday we'll...).
Then they will be in love, and he'll say "Please Please Don't tear your heart from me", because he loves her so much.
Now (he's in love but he can't say it) he's in the underdog position, but Maybe Someday, the you-person will say "Don't tear your heart from me" to him. He fantasises about that too.
@andro666: Good one.
Or maybe, it's about someone who doesn't have the nerve to tell he's in love with this girl (or guy). He fantasises about how it would be if he would have the nerve to say it (And maybe someday we'll...). Then they will be in love, and he'll say "Please Please Don't tear your heart from me", because he loves her so much. Now (he's in love but he can't say it) he's in the underdog position, but Maybe Someday, the you-person will say "Don't tear your heart from me" to him. He fantasises about that too.