Amber Heard has sat impassively through 10 days of Johnny Depp’s $50m defamation against her stemming from their volatile 15 month marriage. Next week, the 36-year-old actor will get to present her version of events in support of a $100m counter claim for nuisance.

Whoever prevails in the end, and perhaps neither, the trial between the pair has been an unedifying spectacle of a horrifying relationship that so far only Depp has had the opportunity to present to the court.

The damage to each of them from their marriage, divorce and subsequent highly public and epic legal battles is conspicuous. Heard walked away with a $14m settlement under California’s communal property no-fault divorce laws, using the threat of a restraining order to negotiate for more, but little in the way of a movie career. Depp, too, lost work, having being dropped by Disney’s Pirates franchise when allegations of domestic abuse against him were made by Heard in 2016.

And for both, the long days of recent testimony have taken the sheen off any sense the public may have that either of the actors’ lives of apparent wealth and glamor were in any way enviable. Instead, it has been a painful story of substance abuse, a deeply dysfunctional marriage and professional woes and plotting.

While Depp consoled himself touring with his band, Hollywood Vampires – a group that Christian Carino, the couple’s former talent agent, testified last week was not a commercial proposition – Heard became an ambassador for the American Civil Liberties Union (ACLU) specializing in gender-based violence.

The court was told that the venerable civil rights group had written the draft of the now infamous Washington Post article upon which this legal action is based, and placed it in the outlet to coincide with the release of Heard’s Aquaman superhero movie. Heard, the ACLU’s general counsel testified, had pressed to go further, identifying herself as an abuse survivor, but her lawyers had excised the passages lest it violated her divorce non-disclosure agreement.

Depp’s generalized argument – that he was docile as a prescription opioid addict, but wrestled with a “monster” when drinking – was coupled with observations made on Friday that household alcohol spending dropped from $160,000 a year during their marriage to “virtually nil” today. Some of that spending, Depp’s accountant testified, went toward Heard’s taste for $500-a-bottle Vega Sicilia wine.

The grim tableau presented to the court peaked this week with images of Depp’s exploded finger after a fight in a rented house in Australia that was re-decorated with blood and broken glass, causing $50,000 in damages.

The unedifying testimony, provided by a succession of aides, agents, concierge doctors, psychoanalysts, housekeepers, doormen and bodyguards, has left the impression of an appalling lifestyle environment that might have been brought to account sooner if there were fewer resources and enablers to support it.

“I would have required that each of them be in an abstinence-only program with random drug tests that confirm their level of sobriety, and I would have required both to do 12-step work,” said New York therapist Dr Darcy Sterling, host of E! Network’s Famously Single.

“The step work is the work that deflates the ego – the arrogance, the propensity to view oneself as a victim with no role in the consequences of their life – so that they could come together without pointing fingers at the other.”

But the trial has provided insight into how celebrity justice might be warped. Expert witness Dr Shannon Curry refuted an implication that her psychological diagnosis of Heard was tainted by being taken out to dinner by Depp and his attorneys, an inference she rejected.

At times what the court has delved into has been bizarre as lawyers sought to prove undue influence. For example, Heard attorney Elaine Bredehoft pressed Curry on exactly who had brought muffins to her practice on the day Heard came for examination. Curry testified that it had been her husband, but that her husband had not known a celebrity client was coming.

“May I clarify what occurred so that we can stop talking about the muffins?” Curry said on the stand. “What happened was that I was getting ready that morning, I frequently bring muffins to the office.”

In the absence of Heard’s testimony, public opinion appears to be so far siding with Depp. According to a Rasmussen Reports national telephone and online survey, 40% of those polled said Depp is probably telling the truth. Ten per cent think Heard is probably telling the truth. Fifty-one per cent are undecided.

Some top celebrities sided with him too. Joe Rogan, host of Spotify’s controversial The Joe Rogan Experience, said that watching the trial was a “cautionary tale” about “believing in bullshit” and offered that the case was good for Depp, but not for Disney. “You got rid of the best fuckin’ pirate you ever had! For a crazy lady!”

Others have fretted that the trial, coming soon after the Will Smith-Chris Rock Oscar slap, has bought the entire construct of Hollywood celebrity into disrepute – as a dissertation on fame as a personal curse – reenacted in a suburban courtroom.

Derek Long, assistant professor of media and cinema studies at the University of Illinois Urbana-Champaign, said that “movie stardom culturally is less important than it used to be by virtue of the fact the media landscape is fractured and everyone constructs their own personal garden of interest”.

Under Hollywood’s old studio system, somewhat reconstructed in the streaming era of Netflix, stars and their images were closely managed and protected by studio chiefs and publicity departments. There were scandals, from Fatty Arbuckle to Charlie Chaplin, or any number of others detailed in Kenneth Anger’s Hollywood Babylon book, but morality clauses and studio infrastructure had ways of managing it in the first place or at least the narrative of it in the press once it had occurred.

“In a pre-#MeToo era there was more of an understanding that terrible things were going to happen and most of their efforts went into damage control, not prevention,” said Long. “Celebrity bad behavior, or scandal of any stripe, is a lot more in the open now and scandal has become a public part of popular discourse.

“Stardom has always been about been about selling the sense that stars are just like us. Implicit in that commodification was good behavior – that stars are just like you at home, they bake cakes and use this or that brand of household cleaner. When all the bad behavior that goes along with stars being human beings, it disturbs people.”