Alice Evans was left heartbroken after her partner's, Daniel Sillwood, sudden death.
Now the mum, who is raising her daughter Imogen alone, has criticised a bizarre law for costing her thousands.
Alice said that she will campaign for a change in the law, adding: "When Daniel passed away, he was the breadwinner. We lost the wage that he brought in. I was left raising a child and running the household single-handedly."
Bereavement Support Payments were introduced in 2017, replacing the Widowed Parent Allowance and other payments. She says she missed out on £45k by not being married.
"Daniel thought the world of Imogen and would do anything for her," she said. "He would come home from his night shift and take her to nursery in the morning, then come back home in the evenings and cook meals.
"He was a family orientated person.” She added: "We just never got married. Maybe we would have one day - we just didn’t get the opportunity."
Nigel Mills, Conservative MP for Amber Valley, said: "The change is going to happen and the catch up payments will be made, it’s just a parliamentary process that needs completing. Sadly that's not always as quick as we'd all like.”
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