Where in the poem that illustrate Prufrock's regret?

THis is difficult to know. Many critics feel that he is expressing regret over a love unrealized. Many believe that Prufrock is trying to tell a woman of his romantic interest in her,[16] pointing to the various images of women's arms and clothing and the final few lines in which Prufrock laments that the mermaids will not sing to him. Others, however, believe that Prufrock is trying to express some deeper philosophical insight or disillusionment with society, but fears rejection, pointing to statements that express a disillusionment with society such as "I have measured out my life with coffee spoons" (line 51). Many believe that the poem is a criticism of Edwardian society and Prufrock's dilemma represents the inability to live a meaningful existence in the modern world.[21] McCoy and Harlan wrote "For many readers in the 1920s, Prufrock seemed to epitomize the frustration and impotence of the modern individual. He seemed to represent thwarted desires and modern disillusionment."[19]