The basic story here is of a speaker who lets his lover know of his feelings and emotions toward her, which in turn results in the lover's repudiation of him: “Trembling cold in ghastly fears / As she doth depart!” Never to be one who spends too much time in self-pity mode, Blake (as speaker?) quickly reverses his bleak situation in the last stanza by rekindling his spirits and assuming the ‘traveler’ loves him as well, because of his/her ‘invisibility’ and silence toward him as she passes. The emotional effect this plays on the reader is playful, taking him/her from one of pity to one of humor, now laughing with the speaker with whom only a few lines earlier he/she was feeling sorry for.
A break away from Blake’s regular themes of lost innocence and political/religious restraint on the human soul, “Love’s Secret” offers the reader a refreshing look at a speaker exploring the themes of the freedoms one experiences by not being in love: freedom from jealousy, freedom from admiration and affection, freedom from desire, and freedom from want. As sardonic as it is, the poem offers up the advice that one is better off not announcing one's affection for another, but rather should remain “silent and invisible.”
As with all things Blake, there is a deeper message here and that is that there is no denying silence. The speaker decided to wear his heard on his sleeve to his beloved, telling her “all [his] heart” and gets left alone and dejected. The opening line is advising, or instructing, “Never pain to tell thy love,” which is much different from the last line which is tongue-in-cheek and a bit of ridicule.
This poem has also been interpreted as the traveler coming in the final stanza as another lover, who the speaker’s beloved turns to for refuge, and who accepts her with no “deny.” Either interpretation is valid and acceptable.