Anna the Adventuress by E. Phillips Oppenheim

Anna sat in a chair in her room and sighed. She was alone, and the mask of her unchanging high spirits was for the moment laid aside. She was a little paler than when she had come to London, a little paler and a little thinner. There were dark rims under her eyes, soft now with unshed tears. For this three weeks had been the hardest of her life. There had been disappointments and humiliations, and although she hated to admit it even to herself, she was in desperate straits. Nevertheless, she was still fighting.

"There is one thing I must concentrate on at the moment," she told herself, "and that is how to pay my next week's bill to Mrs. White. It ought not to be much. I have gone without dinner for three nights, and -- come in."