Love aids the speaker of Shakespeare's "Sonnet 29" specifically by breaking him out of a depressive spiral of negative thoughts, reminding him that though he may not have riches or popularity he is loved by the person he loves and that is more valuable to him than any wealth could ever be. A reader can extrapolate from this to say that love aids people in general by giving them something worth living for even when they have nothing else.
The first two quatrains of this sonnet show the speaker feeling bad about himself, "in disgrace with fortune and men's eyes." The second quatrain details all the things he doesn't have that he is jealous of others for possessing: hope, good looks, friends, etc. It is not until the last two lines of the third quatrain that the poem breaks away from this negative line of thought, turning to the hope that love brings to the speaker. The final couplet concludes, "For thy sweet love remembered such wealth brings / That then I scorn to change my state with kings." These last lines sum up the message of the poem. Ultimately what the speaker has—love—is more important than all the material things he lacks.
Sonnet 29, "When, in disgrace with fortune and men's eyes" by William Shakespeare, is narrated in the first person singular and thus describes the experience of a single person, not of people in general. The sonnet consists of an octave describing the ways in which the narrator is unhappy with his external circumstances and a sestet. In the octave the narrator describes himself as lacking the respect of others, enduring bad fortune, and envying the circumstances and abilities of other people.
After the octave is a Petrarchan-style turn, in which the narrator reflects upon his beloved:
Yet in these thoughts myself almost despising,
Haply I think on thee, and then my state,
Like to the lark at break of day arising
From sullen earth, sings hymns at heaven's gate;
In other words, when thinking about how happy he is in his relationship, the narrator forgets about all of his other troubles and is so happy that he would not even change places with a king. Thus love aids the narrator by making him happy even when other external circumstances are less than ideal.