Benedetta Tagliabue

It's five o'clock on an unbearably hot afternoon in Barcelona. The narrow streets of the old town are deserted in the lull of siesta. The studios of EMBT Arquitectes are in semi-darkness, their wooden shutters barricaded against the sun. In the gloom, half a dozen young architects are putting the finishing touches to a model of the Scottish parliament's debating chamber.

Benedetta Tagliabue breezes in, laughing into her mobile phone as she sweeps up the stairs. Dressed in bright silk and heavy gold jewellery, she throws back her long hair and greets me like an old friend. "Let's see if I tell you good things or not," she says in her sonorous Italian accent, laughing again.

It is easy to paint Tagliabue as a victim: the young bride of a great architect, tragically widowed and left to bring up two children and complete her husband's greatest project.

In reality, Tagliabue, 37, is outwardly unfazed by the harsh hand fate has dealt her; beneath her glamour and charm lies a deep resolve. "This is a situation that was created by our lives," she says, without a trace of self-pity. "I accept everything."

Born in Milan, Tagliabue studied architecture in Venice and then in New York, where she met Miralles – then a rising star – in 1989. By 1992, Miralles had divorced his first wife and business partner, architect Carme Pinos, and set up a new husband-and-wife partnership with Tagliabue in his native Barcelona.

Last summer, after Miralles' death, Tagliabue took charge of EMBT, the 45-strong firm that still bears both their initials. After a year of taking stock personally and professionally, Tagliabue is again entering competitions and has four projects on the go. She has also inherited responsibility for the Scottish parliament in Edinburgh – by far the most prestigious project EMBT has ever taken on.

Tagliabue believes that the crisis-hit project has reached a watershed. "Everything's going much better," she says, pointing out that politicians in favour of the project have had the edge over detractors in recent debates. "Now I think the project has gained a kind of seriousness. You can walk on site, you can see it's something real now."

Miralles never lived to see this turnaround in his building's fortunes. Did the project kill him? Indirectly, perhaps. It may not have caused his brain tumour but it obscured the symptoms. In hindsight, Tagliabue realises her husband had been ill since December 1999.

Miralles put his constant exhaustion and headaches down to stress, and considered giving up architecture once the parliament was complete. "Enric was very, very tired. He was always saying: 'In a few years we have to quit.' [The Scottish Parliament] was very demanding – one problem after another."

Enric was very, very tired. He was always saying, ‘In a few years we have to quit’

Tagliabue pleaded with him to scale back his workload – which included teaching posts in Germany and the USA - but to no avail. "The life he was leading was one of the most stressful lives you could imagine, but this was because he liked it."

It was not until March that he told his wife that he was ill and went to see a doctor. A scan revealed an enormous tumour, which his doctors said was inoperable. "He didn't tell me until the very last day," says Tagliabue. "Everything was normal, then he says, 'I am going to the doctor', and that same night he realises his life could be over."

Some Scottish politicians sensed a conspiracy, claiming Miralles' illness was concealed in the run-up to a vote on whether to ditch the project. In fact, Tagliabue says, they told nobody, hoping to the last that he would survive. He was rushed to the USA for emergency surgery that appeared to have cured him, but his condition deteriorated. He died, aged 45, with his wife at his side in their Barcelona home in July last year.

Miralles never spoke publicly about the problems of the parliament, preferring to communicate through his drawings. But his widow has no such qualms. She is fiercely critical of conservationists who vetoed alterations to Queensberry House. "Queensberry House is a disaster! History is something that needs air, needs to breathe. If you are so stiff, then this will always become dead. In Spain, archaeologists are used to treating the city as a thing alive, and history as something you document or try to explain."

She is dismissive, too, of Bill Armstrong and Alan Ezzi, the two project managers whose resignations added to the air of crisis surrounding the project. Armstrong, who left four months after EMBT won the competition, never believed in the project, she says. "When he went away, he said something bad about Enric's architecture. If he didn't believe in us, he couldn't have been the right manager."

Ezzi, who left this summer, was obsessed with cutting costs but ignorant of the consequences, says Tagliabue. "He was really trying very hard, very stubbornly, to make this project cheaper, and sometimes the proposals were unrealistic. It would be fantastic to have a completely different structure, but who will pay for the recalculation, how much time we will need to do that? Maybe he realised what he was proposing was not useful enough."

Tagliabue appears able to rationalise the project's crises in a way her husband – who was deeply hurt by the criticisms – was perhaps unable to. "You have to be strong enough to take the problems with a certain philosophy," she says. Although Miralles found the criticism hard to comprehend, Tagliabue chooses to interpret it positively. "If people are talking about it, it must be interesting," she says. "The worst is indifference."

Does she dislike the way the press have painted her as the widow of Enric Miralles?