Countries, like people, find bad habits hard to break. A smoker may resolve to quit but reach for a new cigarette. A lone drinker may start with orange juice and slowly add vodka. And a departing member of the EU may declare it is seeking a special new partnership with its strongest allies then spend two years trying to divide, deceive and shaft them.

When Ireland’s foreign minister, Simon Coveney, tweeted on Sunday that Britain’s calls for a time-limited or unilaterally breakable backstop “are not backstops at all and don’t deliver on previous UK commitments”, he echoed the frustration across the EU. The concern is not that the UK holds a different opinion, it is that it is reneging on the guarantees it has already made. As the negotiators brace themselves for a lock-in at the last-chance saloon, the underlying problem is less about the backstop than the EU’s chronic lack of trust.

There is a reason why Britain is being dragged kicking and screaming from the backstop to the withdrawal agreement. Since the start of this process, our government has confirmed every European fear and British stereotype. The UK has sought to divide and rule, bypassing the European commission and playing member states off against one another; ceaselessly demanded unique privileges unavailable to either members or non-members; and continued to insist upon fantasy technology at the Irish border to prevent the return of all-too-real sectarian violence.

Our long reputation has always preceded us but, immediately after the referendum, the EU held out genuine hope that the government might behave reasonably. Certainly, Britain’s official narrative centred around building goodwill and demonstrating good faith. But, in reality, Theresa May quickly compounded tactical errors with pointless offence. The 2016 “citizens of nowhere” conference speech horrified EU diplomats, who also objected to the threatening tone of the Lancaster House speech and Article 50 letter. In May 2017, the prime minister even accused “bureaucrats of Brussels” ​of meddling in the UK election. Boris Johnson’s rhetoric about punishment beatings and whistling for money, and Jeremy Hunt’s likening of the bloc to a Soviet prison did little to help.

The EU expected domestic Tory theatre, but ministers’ hostile language has also bled into personal relationships. Johnson, David Davis and Dominic Raab have all been deemed abrasive figures, and EU officials report numerous breaches of courtesy and protocol. Character and personality matter, and British arrogance has not won friends or influence.

The Irish position, in particular, has faced open scorn in the British media. In the past few weeks, UK officials have dismissed and belittled Dublin’s concerns in off-record briefings, while senior MPs have accused the country of exaggerating the border issue or fabricating it altogether. Irish figures are well accustomed to such condescension and have bristled at yet another outbreak of groundless British exceptionalism. The rot set in early, when the government demonstrated its intention to subordinate the Good Friday agreement to UK-only trade deals. Ireland’s dismay solidified last December when then-Brexit secretary Davis declared the backstop was unenforceable. As for May, she paid no attention at all to the island of Ireland until she lost her parliamentary majority and bribed one of its parties to rescue her.

It is often unclear if the UK is trying harder to hoodwink the EU or itself. Ministers have repeatedly called for things they must know to be impossible. Davis promised that a trade deal would be ready to sign next March; May insisted free movement in its current form would end during the transition period; and now Raab declares that he can unilaterally terminate a backstop that both sides agreed will last “unless and until another solution is found”. In sacrificing trust, we have also sacrificed credibility. After two long years, the government not only appears duplicitous, but demonstrably out of its depth.

Brexit’s slow unravelling was both predictable and avoidable. Officials frequently remark that if they had trusted the UK’s motives and competence, they would have afforded the government more leeway. But instead of building bridges, the UK quickly burned them. The EU now suspects the government will do everything it can to wriggle out of the backstop, and is determined to thwart Britain’s faithlessness with a watertight withdrawal treaty. If, in the final weeks, the EU is holding our feet to the fire, it’s because we have shown it that it must.

• Jonathan Lis is deputy director of the thinktank British Influence