Marriage is not only – or even mostly – a declaration of love, especially when ambition and money are involved. It’s an alliance, a joining of powers. In the years since the Obamas moved into the White House, their only peers as an aspirational couple have been Jay Z and Beyoncé. Their relationship has been key to their pre-eminence: each partner magnifies the other’s glamour and significance. But where most famous couples, assuming they make their relationship public, take care to craft an image of togetherness, Beyoncé draws attention to marriage’s doubts and discontents. It has become a defining part of her persona; perhaps her great subject.

Her best albums explore this through different prisms. On B’Day (2006), money is both a metaphor for the dynamics of a relationship and a necessary strategic calculation when two wealthy people get together. “Upgrade U” offers a partnership that’s as much financial as romantic (“I’mma help you build up your account”); the litany of updates she wants to make to Jay’s wardrobe is both a metaphor for how relationships stretch people and a description of their luxurious lifestyle. In “Ring the Alarm”, infidelity is, literally, burglary, an occasion for sirens. (The album contains some of her best vocal performances, with the excitement of a musician testing the limits of her instrument, like the repeated “Yes!” that climaxes “Suga Mama”.) On Beyoncé (2013) it’s sex as physical act and emotional expression. It ranges from the playful sense of her body as bounty in “Blow” to the insecurity that lurks behind the limousine shenanigans in “Partition” (“I just want to be the girl you like/The kind of girl you like is right here with me”). On her latest, Lemonade, it’s the fallout from infidelity.

It’s impossible to say to what extent this music is autobiographical, and it doesn’t really matter. Like Janet Jackson and Madonna before her, Beyoncé has made certain biographical facts a key part of her persona. For Janet, it was the escape from the Jackson compound to Minneapolis depicted in the “Control” video; for Madonna, the death of her mother and her difficult relationship with her father. In Beyoncé’s case it’s a father who was also her manager and a husband who’s also her business partner. There’s a special excitement when a famous person opens up her life in this way: the ordinary conflicts assume a mythic size and sweep. At the same time the star is humanised, like us. Their songs and albums are not merely the latest items off the conveyor belt, but new chapters in an ongoing story.

When Beyoncé’s music lacks this personal element she subsides into dull professionalism, as in 4, a good-enough collection of songs that lacks the special jolt when pop music meshes with persona. Earlier in her career – the Destiny’s Child days – her main limitation was a rather narrow sense of entitlement, asserted but not enjoyed. That’s why “Bootylicious” was such a breakthrough: Beyoncé was as self-possessed as ever, but with a new capacity for humour and pleasure. The professionalism puts some people off: they see her as another former child performer dutifully hitting her marks. But that Virgo self-discipline and mania for order – this is the woman who famously archives every extant photo and bit of footage of herself – is fascinating in its intensity of expression, especially when it butts up against things it cannot control. Like feelings, or a straying husband.

Beyoncé makes interesting use of that treasure trove of images. On one hand there’s a sort of pettiness to the former child performer who makes so much of a talent show she lost, as she does on “***Flawless”. (She certainly won in the long run.) But then the footage she includes of her father in the Lemonade film makes personal the ambivalence expressed in “Daddy Lessons”: as a child, even family intimacy was performed for the cameras. In this she’s an emblematic figure for anyone who curates a self on social media and for the generation of kids growing up in semi-public on their parents’ Facebook pages.

Lemonade is far more concise than its predecessor, with a clear narrative arc from suspicion to anger to wary forgiveness. The “visual album” format seems intended, at least in part, to force us to experience it as a whole, not just a collection of tracks. The concision applies to the song lengths as well: most of the album’s twelve songs run under four minutes, without any of the interludes that stitched Beyoncé together. One of the most impressive things about it is its generosity: “6 Inch” is an empathetic tribute to the other woman’s beauty and industry (“She worth every dollar and she worth every minute”); “Love Drought” struggles to acknowledge the straying partner’s good intentions (“I’m trying to be fair/and you’re trying to be there, and to care”). It’s this emotional fullness that gives the moments of fury such punch: the contemptuous way she spits out “Try not to hurt yourself,” the sudden access of anger in the measured piano ballad “Sandcastles” (“Bitch, I scratched out your name and your face”). “Don’t Hurt Yourself” is the apogee; it’s an illustration of her collaborative approach to building music (chorus sung by Jack White; drum sample from Led Zeppelin) and a brilliant, mocking evisceration of male rhetoric. “When you hurt me, you hurt yourself,” Jack White sings on the first chorus: he’s every man who uses a woman’s identification with a relationship as a licence to get away with shit. When Beyoncé voices the same words in the second chorus, mixed so her voice is almost indistinguishable from White’s, it’s a reproach for the man’s failure to make that identification, for his selfish refusal to perceive them as a unit.

It will be interesting to see what the future of this marriage – this alliance – is. Beyoncé is certainly the prime mover now as an artist; Jay Z’s last good album is five years behind him, and that only with Kanye West to prod him along. Whatever happens, she is likely to make compelling music out of it.