The Peacock Summer book by Hannah Richell

At twenty-six, Lillian feels ancient and exhausted. Her marriage to Charles Oberon has not turned out the way she thought it would. To her it seems she is just another beautiful object captured within the walls of Cloudesley, her husband's Chiltern's manor house. But, with a young step-son and a sister to care for, Lillian accepts there is no way out for her. Then Charles makes an arrangement with an enigmatic artist visiting their home and her world is turned on its head. Maggie Oberon ran from the hurt and resentment she caused. Half a world away, in Australia, it was easier to forget, to pretend she didn't care. But when her grandmother, Lillian, falls ill she must head back to Cloudesley. Forced to face her past, she will learn that all she thought was real, all that she held so close, was never as it seemed.