Hell hath no fury like a woman scorned. Or so, at least, said someone who had clearly never met George Osborne. Such is the man’s capacity to hold a grudge that he apparently will not rest until Theresa May is “chopped up in bags in my freezer”, according to a juicy new profile in Esquire magazine. On election night, when the scale of the disaster she had presided over became clear, the new editor of the Evening Standard reportedly texted “hahahahahahhaha” to a friend even as his former colleagues were losing their jobs.

So far, so very much like something out of an episode of Dr Foster, the wildly excitable BBC drama about a wronged wife out for vengeance, which has just returned to our screens. And undeniably, all this public bunny-boiling has turned Osborne’s paper into a must-read. Yet the Tory psychodrama now playing out in front pages is starting to feel unhealthy for all concerned.

The trouble is that it’s still unclear which side of the fence George Osborne is on. Is he genuinely a journalist now? If so, he ought to be above petty emotional vendettas? Or is he still a politician at heart, using this job as a way of continuing politics by other means? In a world where the line between activism and journalism, driving events and reporting them, is already dangerously blurred, this is surely an ambiguity too far.

Osborne is now in the grim position of watching arguably less able but more popular rivals make a hash of things

Yes, it was thrilling at first to see Osborne replaying old cabinet battles in public, spilling the beans about what went on behind closed doors. For many remainers, it has been deeply comforting too to see his paper making such a sparky case for the benefits of immigration and openness to the world, trying to hold the centre ground and giving the Eurosceptic tabloids a run for their money.

Talk of Osborne now having a gun and not being afraid to use it against old enemies will, meanwhile, seem like jolly spectator sport to many on the left. What’s not to like about Tories fighting among themselves? Some will think it hopelessly naive, in a world where Steve Bannon can describe returning to Breitbart from the White House as getting “my hands back on my weapons”, to imagine the liberal media shouldn’t fire back.

But as time wears on, the nagging feeling that no good can come from allowing newspapers to be used like this grows. Osborne is right to argue that the British press (although not British broadcasters) have always been openly partisan vehicles for expressing their editors’ and proprietors’ personal views and influencing political decisions. What is new, however, is the appointment of an editor who has so much personal skin in the game. If journalism is the first draft of history, then the history of seven years of Tory rule, and its consequences for Britain, is being edited in front of our eyes by someone who was far too deeply involved to have any sense of objectivity.

The most revealing passage of Esquire’s interview in some ways wasn’t about May, but about the Grenfell tragedy, which the former chancellor evidently feels was not about cost-cutting so much as “a massive failure of fire standards over many, many years”. It may be, of course, that the public inquiry proves him right. But there is something deeply awkward nonetheless about the man so recently in charge of the nation’s public spending having the last editorial word on this.

Overlooked by the shell of Grenfell tower, a silent march is held in memory of the victims of the fire. Photograph: Chris J Ratcliffe/AFP/Getty Images

Imagine, too, if all the energy expended on May were channelled into in-depth investigations of, say, how London’s broader housing market was allowed to spiral so wildly out of control, or how the city will function when essential workers can’t afford to live there, or even how a Brexit referendum that will profoundly affect the City ever came to be held and lost. The ex-chancellor surely has some unique insights but strangely enough, the inside information we’re getting tends to be the stuff that makes everyone else look bad.

Osborne’s defence against the charge of stalking his old party is that his paper attacks Jeremy Corbyn too. But somehow the paper’s salvoes against Labour lack the same energy. True vengeance, after all, requires an element of humiliation that Osborne never experienced at the hands of Corbyn. It’s the being scorned – dumped, mocked, rejected – that gets the fury ratcheted up to really hellish levels.

Think of the hunger in parts of the Corbynite left to deselect Blairites, which isn’t just about ideological purity but about getting their own back for years of being isolated and disparaged. Think even of the new spin Jean-Claude Juncker put this week on his longstanding desire for a more federalised Europe, arguing that Brexit could be a springboard; see, Britain, you only ever held us back anyway! It had shades of the deserted spouse, getting her own back by cutting her hair in that style he never liked, clearing out his old junk and generally taking advantage of her new freedom. In politics as in divorce, it takes people who were once intimately connected to really press each other’s buttons.

Yet one can’t help suspecting there is more to Osborne’s apparent fixation with May than their past clashes within cabinet or the condescending way in which she sacked him, with one last lecture on getting to know his party better. It may look as if he’s having tremendous fun, picking off old enemies at a distance like a sniper, but those who know him well suspect he’s missing Westminster more than he lets on. May is a living reminder of everything that went wrong for him – Brexit, the personal defeat not only of David Cameron but of the Tory philosophy he and Osborne represented, the rise of Corbyn, the threat of another recession looming – and of what he did not personally achieve.

Osborne knows he could easily have been a contender for the Tory leadership, but didn’t run in 2005 or in 2016 at least partly because he was self-aware enough to understand that he wasn’t sufficiently well-liked to win. Rather like Hillary Clinton, whose new memoir seethes with frustration, Osborne is now in the grim position of watching arguably less able but more popular rivals make a hash of things.

And we all know how frustrating that feels. Parliament pressing blindly on towards the edge of the Brexit cliff, MPs only too aware in many cases of the damage they’re about to do to their constituents’ lives but seemingly incapable of finding a way out; the economy faltering, the social fabric tearing, the country divided. Who wouldn’t leap at the chance to do something about it, if we could?

But Osborne now needs to choose his weapon: politics or journalism, but not both. If the honest answer is politics, then he should return to Westminster. If it’s journalism, then he should do it without fear or favour, using his inside knowledge to investigate and explain how on earth we’ve ended up here – which is as much his and Cameron’s fault as May’s. Revenge may be a dish traditionally served cold. But there’s something horribly unhygienic about dishing it up from a newspaper.

• Gaby Hinsliff is a Guardian columnist