A leading scholar has been given access to thousands of previously unpublished letters to Philip Larkin from his long-term lover Monica Jones that reveal the pain of her partnership with the poet over four decades.

This photograph of Monica was taken by Larkin in Leicester in 1947.Her thoughts are contained in boxes filled with 2,400 letters to Larkin that she left to the Bodleian Library, Oxford, with the instruction that they were to remain closed until decades after her death. She died in 2001, aged 78.

Professor John Sutherland, a leading scholar and Jones’s close friend, has been given unrestricted access to the collection. He told the Observer that the letters were represented “virtually everything that she wrote to Larkin over 37 years of separated love”. Larkin and Jones were both born in 1922 and studied at Oxford, although they first met at the-then University College Leicester not long after the second world war. He was a deputy librarian and she was an English lecturer with peroxide hair. Larkin transferred to Queen’s University Belfast in 1950 and then later to the University of Hull.

A play by Ben Brown, Larkin With Women, which premiered in Scarborough in 1999, tells of the poet’s tangled relationships with Monica in Leicester, and two other women, Maeve Brennan and Betty Mackereth, in Hull. But Larkin saw Jones as his intellectual equal, unlike his other lovers. He dedicated his collection, The Less Deceived, to her, and bequeathed to her the bulk of his estate.

Sutherland, professor emeritus of modern English literature at University College London, was taught by Jones, and attributes his career to her. He wrote her obituary in the Guardian, and is now finishing a book on Jones, based on the letters, to be published next year by Weidenfeld & Nicolson.

In his Guardian obituary, Sutherland said that Larkin and Jones became lovers in 1950, just before he went off to a post at Belfast. “Monica was doggedly faithful to Philip - despite the opportunities available to a single woman of her gifts and attractions in the 1950s and 1960s. Philip was serially unfaithful to Monica: unable, apparently, to be creative as a poet without the tensions of infidelity and uncertain commitment in his emotional life. He would visit her - usually at weekends - en route to and from his aged mother, in Loughborough.” He added that “of Larkin's harem, Jones was the woman with most claim to be his intellectual equal”.

Poet and journalist Trevor Breedon, who was taught by Jones at Leicester in 1971-72, and studied the Romantic poets with her, recalled his academic tutor as “quite flamboyant, like a favourite eccentric aunt … her hair was flaming ginger in those days and she wore a flowing cape and a mixture of black, purple, orange and red. She never spoke of Larkin, of course. But I remember that one of the few items on her office noticeboard was a flyer for All What Jazz. [A collection of Larkin’s writings on the subject].”

Sutherland said no other biographer of Larkin had enjoyed access to "these letters”. Some envelopes still bear her lipstick marks. The correspondence ends in the early 1970s when they got telephones. Sutherland said: “After that, he would telephone every night. When her health collapsed in the early 1980s, she moved in with him.” Larkin died in 1985. Following his wishes, Monica destroyed his diaries after his death, and lived on in his house in Hull for another 15 years.

PHOTOGRAPH: LARKIN ARCHIVE, HULL