Helen Ann Simpson was born at Gibraltar, probably in 1793 or 1794. Her mother's name is unknown. Her father, James Simpson, was the United States consul general at Tangier. On 11 June 1840 in London, England, she married Peter Wilson, superintendent of the civil hospital at Gibraltar. He would later become colonial surgeon in New Zealand, in 1849. The couple had no children, but raised Patricio, Peter Wilson's son from a former relationship.
Helen, Peter and Patricio Wilson embarked on the Slains Castle on 13 September 1840, bound for Port Nicholson (Wellington), New Zealand. Soon after their arrival they boarded the schooner Elizabeth for Wanganui, which they reached on 27 February 1841. For the next seven years Peter Wilson worked as a medical practitioner in Wanganui. In the absence of professional nursing assistance Helen Wilson often took on this role. The invaluable support she gave to her patients and friends is reflected in the letter of one young woman, Jessie Campbell, to her mother: 'my kind friend Mrs. Wilson did everything for me that you could have done, she came every day to dress the baby until I was strong, in short as I often told her, she was both mother and sister to me. …except our own family, I have no relation for whom I have such a regard.'
The Wilsons purchased several properties in the Lake Kaitoke area, and took a prominent part in the social life of Wanganui. In December 1847, however, at Helen Wilson's instigation, the family moved to New Plymouth. The move may have been prompted in part by a desire to live near to Donald McLean, the future chief land purchase commissioner and native minister, whom the Wilsons had met in 1844. Helen Wilson became a close friend and confidante of both Donald McLean and Governor George Grey. She addressed McLean in her letters as 'My dear Son', and their close relationship is evident in her affectionate, sometimes bantering tone: 'I hope you behave yourself properly by Not reading in Bed – keeping your room tidy – not making too great a splash at your morning ablutions – and of all things keeping to regular hours', she upbraided him on one occasion.
Well educated and an avid political observer, she wrote frequently to McLean keeping him informed of the political situation in New Plymouth and the surrounding area, and was forthright in expressing her opinion. In response to reports of the governor's apparent willingness to make peace during the Taranaki war of 1860, she wrote: 'I will not allow myself to believe that our good Governor will allow himself to be led away by a set of Exeter Hall Boobies…. I find my scotch-english-spanish and Barbary blood quite on the high'. Helen Wilson also recorded her life by sketching. One of her sketches is now held at the National Library of Australia, Canberra, and another at the Alexander Turnbull Library, Wellington.
When martial law was declared in New Plymouth in February 1860 the Wilsons were forced to abandon their home at Te Henui, which was later destroyed, and rent accommodation in town. After hostilities ceased they remained in rented premises in New Plymouth, where they continued to play an active part in religious and social life. After Peter Wilson's death in December 1863 Helen Wilson stayed for a time at Grey's official residence in Auckland, before renting part of a house in New Plymouth. Two years later she moved into a cottage she had had built, and had named Calpe Cottage, Calpe being an ancient name for Gibraltar.
Helen Wilson continued to take an active interest in church and local welfare work until her death, at New Plymouth, on 24 June 1871. Her obituary in the Taranaki Herald recalled her as 'most charitable, and…exceedingly active in promoting the social welfare of those around her.' She had provided strength, unity and assistance to other women during the early years of European settlement in Wanganui and New Plymouth.