Picture a scene where a man and a woman have fallen over a cliff face. Just like in the movies (arguably with a role reversal) the woman holds on to the cliff for dear life with one hand, her other hand the only thing stopping the man from falling to the icy, rocky sea below.

Probably fairly obviously this is not exactly what the poem about, rather it is a metaphor for both these characters being on the edge of life and death, unsure of whether to fight for everything they're worth or let go of the Hell they live. The woman still at least has a grasp of the real world, but the man is not so lucky, she is all he has, the only thing stopping him from falling of the end of the world into oblivion.