6 ideas
The lover's discourse is not a story but a set of 'figures': recurring, recognizable outbursts (waiting, jealousy, the 'I love you', the wish to die) that seize the lover in the moment, the way an athlete's body is caught mid-gesture. A figure exists whenever someone can say 'That's so true! I recognize that scene,' so the figures are defined by recognition rather than by definition.
The fragments are deliberately arranged in arbitrary alphabetical order so they cannot build into a love story with a beginning, a crisis and a resolution. Refusing plot keeps love from being given a moral or a meaning, and matches how love is actually lived: as non-sequential episodes that repeat, not as a progression.
The lover is the one who waits; the loved one is the one who never waits. Barthes breaks a single wait for a phone call or a meeting into staged acts: anxiety, anger, imagined abandonment, then collapse into relief when the other arrives. Waiting shows how power moves in a relationship, because the person made to wait is structurally the dependent one.
In love, absence runs only one way: the one who stays speaks the other's absence and invents it through discourse, talking to someone who is not there. The lover handles this by manipulating the absence, alternately forgetting and summoning the other, and so turns a painful lack into a scene that can be rehearsed.
'I-love-you' works as a single indivisible word, a proffering that describes nothing and conveys no information; it is uttered for the sake of the utterance itself. Its expected reply is the same phrase returned, and answers like 'I know' or 'Thank you' fall flat because they treat the words as a statement rather than an act. Yet Barthes also lets an imperfect or unexpected reciprocal answer bring jubilation, so the returned phrase is the ideal reply rather than the only one that works.
Barthes argues that love speech has become extremely solitary. Science, knowledge and art ignore or scorn it, and it is now less acceptable than sexual discourse, which gets endless analysis and legitimation. Sentimentality has become the new obscenity, so the book's task is to give that disreputable speech a place to affirm itself.