Me i have zero idea on how to do i know how to do the rest of the questions just not this what does she mean?

The speaker says that it is better for the person that she is speaking of in the poem to forget about the speaker and smile "than that [the person that the speaker is speaking of] [to] remember [the speaker] and be sad." In the poem, just before the line "than that you should remember and be sad," the speaker states "Better by far you should forget and smile," clearly evidencing that the speaker feels that it would be better for the person the the speaker is speaking of to forget about the speaker and feel happy than to remember the speaker feel unhappy. Because the speaker clearly states that she would rather not be remembered by the person that she is speaking of in order for that person to be happy than the person that she is speaking of the remember her and feel sad, it proves that the speaker feels she feels it is better for the speaker to be forgotten by the person that she is speaking of in order for that person to be happy "then that [the person the speaker speaks of] should remember [the speaker] and be sad.