The poem builds one extended metaphor: life is a cliff, and a woman is standing on it, holding on. At first the weather is mild. Drizzle and snowflakes wear away small bits of rock, and she copes. The speaker insists that this isn't giving up, just the daily work of staying put.
Then the weather changes. Rain pours, hail pounds, and the cliff "cracks and groans." Here the speaker seems to share the woman's confusion and quiet dread. She expected the usual small hurts, not this. The line "it's not supposed to be this way" sounds almost like a child's protest, though the next line accepts that hard things happen to everyone.
The mood is steady and weary, with a calm that feels slightly ominous. The short closing couplet, "life is a cliff / and a cliff crumbles," lands bluntly. It leaves us unsure whether the woman will fall or simply survive in a changed landscape.