Lyric discussion by Lilm0nkey 

Cover art for Bridge Of Light lyrics by Pink

As this is used in happy feet 2 when the child (I haven't really seen the movie just the part with this in) is stood on a cliff being told 'no' by his father while all the mothers are below him, I think it is p!nk (the mother) telling the child (penguin) not to commit suicide. The lines 'when you think hope is lost' ; 'you can't give up the fight' ; 'you gotta be strong tonight' ; 'you're convinced that your all alone' they all make you think that the kid could be contemplating suicide and she is telling him not to. This would also make sense as when she 13 she was also contemplating suicide.