 O'Hanlon died from breast cancer at age 43, having been diagnosed three and a half years earlier.In that time she became a breast cancer activist who organised a conference as a way of bringing activists together to talk about breast cancer, raise awareness and draw attention to the mobile breast cancer screening units.O'Hanlon also co-founded the West Belfast Festival called Feile an Phobail and devoted many years to its success, and she performed voluntary work for adults with Down's syndrome.