In 1932, Picasso was engaged in an affair with Marie-Thérèse Walter. ‘Picasso 1932 – Love Fame Tragedy’ at Tate Modern, which runs until September, puts on display everything that Picasso made in that year – bold, brilliant and profoundly moving.

The scope and quantity of Picasso’s output before 1932 is remarkable: the red-hued vitality of his bullfight scenes, the carnivalesque spontaneity of his paintings of circus troupes, and the ‘Blue Period’ in which grief is given rich expression. This exhibition, with its limited time frame, brings a direct focus on that virtuosity – the sheer degree to which Picasso could create in a vast range of communicative modes, genres, forms and styles.

There is primitivist sculpture here, cubist abstractions, and fine, delicate sketch work – and of course the familiar mangling of line and colour popularly associated with Picasso. But it is the paintings of Marie-Thérèse herself which make this exhibition so important.

Picasso’s conceptualisation of desire is complex – in ‘Girl before a Mirror’ for example, he inverts the lyric notion of the love relation as a perfect mirroring of two selves and shows it for what it really is – a chaotic layering of desire, lacerated by uncertain feeling and tortuous self-compromise.

Picasso’s second wife, Jacqueline Roque, once remarked: “In each period, in fact with each different woman, he had a sort of leitmotif. Like in Wagner, you can hear it in his work, the leitmotif that introduces each character, in Picasso you can see it.”

Marie-Thérèse is given the most extraordinary leitmotif. In all the paintings of her, situated in a chaos of limbs, vulvas and open sores, there is always a flash of yellow, a flash of golden blonde hair – her golden blonde hair.

For Picasso, love is an absolute value – there is no room for compromise in the love relation: “When it comes down to it, there is only love. Whatever it may be.” That is how love presents itself to us – a force that comes from elsewhere. It gives itself to us. And we have no choice. We have no choice at all.

Picasso saw this clearly, expressed it clearly. Just look for that flash of yellow hair, the ecstasy and abandon of the brush strokes, and you can see how that force gave itself to his life and that he had no choice in the matter.

He once wrote: “To me there is no past or future in art. If a work of art cannot live always in the present it must not be considered at all.”

And I think that this is true of love too. There is no past or future in those paintings of Marie-Thérèse – only golden hair and the summer of 1932.