I think that the explanation of Parker's solace lies in the images she employs. These images help to bring out the idea of the difference between the sensitive and caring individual and the dismissive and almost heartless condition of the world around them. This dynamic is explored in the three images, helping to construct a distinct difference between what the individual experiences and what the world dictates to that individual.
The tender beauty of the rose is one that dies or is extinguished. Parker's construction of the world's response is one of dismissiveness, suggesting that another will grow and its unique beauty will not be missed. The bird that was "brought down to die" is another example. The world discards the sadness intrinsic to this condition, suggesting that there is nothing with which concern is needed. When the speaker, conceivably Parker herself, suggested that her own condition can be absorbed by the state of being in the world, she flees such a condition. This helps to bring out the poem's primary purpose in exploring the difference between the reality of the individual and the condition of the world around them in terms of their own unique appreciation.