In 2007 you wrote a piece for the Guardian in which you described learning more about your cousin Leonora Carrington and her work. How did you feel making such a remarkable discovery?

Discovering I had this exotic, intriguing cousin who had lived such an extraordinary life was very exciting. My day job is writing about families (for the Guardian Family section), usually other people’s families: now, suddenly I discovered a wonderful story within my own family. But making the decision to go to visit her was quite scary, because she wasn’t in touch with any of our relatives in England any more, and some of them thought she wouldn’t be particularly pleased to have someone turn up from this family she’d left so many decades ago. So I went with some trepidation, not really knowing what to expect when I arrived. In fact she couldn’t have been more welcoming. The moment I heard her voice on the phone, I knew we were going to be friends.

She was described by sections of the family in the UK as ‘an artist’s model’

When someone leaves their family – turns their back on them, walks away from them – that’s a very big statement. I think many people in our family were very hurt by Leonora’s disappearance, and I think the easiest thing for some of them to do was forget about her or downplay what she was doing as an artist. But then again, the truth was that our family weren’t the sort of people who would be following the ins and outs of the Surrealist movement – I’m sure my grandmother, who was the person who called her ‘an artist’s model’ would have had no idea who Max Ernst was. I don’t think she was being malicious in any way – in fact she was very fond of Leonora, and was sorry she had left – but she really didn’t know what she’d got up to after 1937. In those days Mexico, where Leonora ended up in 1942 and where she spent the rest of her life, seemed a lot further away than it does today.

You have described Carrington as ‘fiercely independent, instinctively feminist’. Some in the arts establishment remembered her as muse to Max Ernst rather than a creative force in her own right. Have things changed?

The Surrealist movement was a movement centred on male artists: they adored women, but they didn’t see them as equals. They were of their time – this was the 1920s and 30s – but I think there was definitely some irony about the fact that they thought they were revolutionary and mould-breaking, and yet they saw women through such a traditional prism, as lovers and muses, as femmes enfants. Leonora, who was 20 when she eloped with Max Ernst and was parachuted into the centre of the Surrealist circle in Paris, was the femme enfant par excellence. But despite the fact that she was so young – most of the men, like Ernst and Picasso and Dali and Breton, were much older than her – she definitely did challenge them. She refused to be cowed or obscured by them, she wouldn’t allow herself to be merely a handmaiden of Surrealism. In a sense she escaped twice: the first time was from our family, but the second time was from Ernst and the Surrealists, although she did truly love Ernst. Have things changed? Well, Whitney Chadwick in the 1980s did a great deal to unearth the women artists of Surrealism; but in general terms it’s hard not to think that women still have a raw deal in art to this day. Leonora once said to me, why have women writers had it comparatively easy, while it’s been so very difficult for women in art? It’s an interesting question.

On another floor in Tate Liverpool is Max Ernst’s Dadaville c.1924. Would she have seen it as significant to share gallery space with her former lover?

I’m fairly sure Leonora would have said she had no opinion either way: she would have said it was of no matter whether a gallery had Ernst’s work in as well as hers. She often said to me that she owed Max a great deal, because he really provided her with the education she had failed to get at the convents where she had been at school (she called it ‘diseducated’) in England. He taught her about literature, he taught her about art, he taught her about ideas, he taught her about a new way to live. But Max learned things from Leonora as well: his art, especially through and in the aftermath of those years he shared with Leonora, is littered with references to what she gave him, to the difference she made to his life. 

Leonora produced a huge variety of work, from painting to short stories – and many things in between. Do you have a favourite piece of her work? Why? 

The House Opposite 1945, which hangs on the walls of West Dean, her friend and patron Edward James’s home in Chichester in Sussex, is one of my favourites of her paintings. It dates from 1945, and I think Leonora did her best work in the 1940s. I love this piece because it seems to sum up so much. It is set in a cutaway house, with lots of figures, all female, floating through the rooms. Three of them are cooking something up in a cauldron, another is sitting at a table. A third is falling headlong through the floorboards from the upstairs floor. A fourth is walking up a staircase into a little room at the centre of the house where a young girl is sitting with her head in her hands, submerged in a pond of water, a rocking horse behind her. Upstairs in another room someone is in bed dying. I think all the figures in the painting are Leonora herself; when she was dying in 2011, I thought often about this painting. But the thing is that, in every room, there’s always an escape: there’s always a way of disappearing, of getting out, of moving to another plane. Nothing was rigid in Leonora’s world: everything had fluidity and possibility. In the bottom right corner of the painting, there’s a tiny figure beneath the house swimming away. That’s Leonora now.

In 2010 you co-curated an exhibition of her work (and that of her contemporaries Remedios Varo and Kati Horna). You have said that you wanted that exhibition to result in ‘the art world … [taking] a fresh look at these European outcasts in Mexico’. Do you think, with this solo show of Leonora’s, that that has happened?

I think every show helps boost an artist’s profile, and Leonora was in great need of having her profile boosted at that point.  Before that, the last exhibition of her work in the UK had been at the Serpentine Gallery in London in 1991. Since 2010 there has been another show in Dublin in 2013, and now this exhibition at the Tate in 2015. So I would really like to think that the Chichester show in 2010 helped put her back on the map.

She spoke about how ‘one must create a personal geography’. What do you think she meant?

Being true to herself was fundamental for Leonora: she thought this searching for the truth in ourselves is crucial. She wasn’t someone who could put up with things being not right, with feeling that she wasn’t in the right place, and that’s why she had to leave our family and to leave the UK, because to do the work she had to do, and to live the life she had to live, she needed to be in a different sort of place entirely, and she needed to be surrounded by different people. Many people put up with the landscape they find themselves born into, and some have no choice: but Leonora did have a choice, although it wasn’t an easy one, and she decided to get out. It’s quite an unusual thing to have to escape the shackles of advantage and a huge fortune; usually in life people escape poverty and disadvantage. But with the advantages of her life came compromises she couldn’t accept. I think her choice showed truly extraordinary strength of character: not many people would have given up all she had to plunge herself into a life of war, uncertainty, poverty, friendlessness and frankly, at times, terror. But the one thing she was sure of was that, whatever happened, she wasn’t going back.

What is your favourite, or most abiding memory of the meetings you had with Leonora? 

I suppose what I remember with most fondness is the long days we had together at her house in Mexico City. Because she left England so long ago, and went so far away, she had lived a life without any extended family. Of course she had her sons, and their children, and they were incredibly important to her: but she had no wider family, no nieces or cousins or great-nieces. I think she liked just having someone around, and because she seemed happy to have me there, I was always very happy to be with her. Life with her was always fun: there was always something amusing going on, or some drama we were following, in the newspapers or in the street or in the neighbourhood or among her friends. She showed me a whole new way of looking at life, as we sat there at her kitchen table, and it’s changed me forever. I feel I carry her in my heart every day, and I’m incredibly grateful for that.

Leonora Carrington is on display at Tate Liverpool from 6 March – 31 May 2015