A 62-year-old postmenopausal woman presents to her general practitioner with complaints of severe hot flashes that significantly affect her quality of life. She has a history of breast cancer diagnosed three years ago, which was treated with surgery and chemotherapy. Her cancer was estrogen receptor-positive. She is currently on tamoxifen as part of her ongoing treatment. She is concerned about the use of hormone replacement therapy due to her cancer history. What is the most appropriate management option for her hot flashes?