Native Australian Helen Reddy was a fixture on the pop charts in the early to mid '70s, with more than a dozen top 40 hits. Best known for the iconic "I Am Woman," she had little respect from the teen audience represented by the main characters in Cusp. That song - and its over-30 performer - was for their mother's generation.
"Ain't No Way to Treat a Lady" hit the Billboard charts at the end of the summer of 1975 and rose as high as #8 (#1 adult contemporary). It continues Reddy's theme of speaking up as a woman, not accepting poor treatment from a man.
From Cusp:
"I enter the kitchen where Mom is on the phone but still moving around. Helen Reddy’s “Ain't No Way to Treat a Lady” plays quietly in the background as she opens cupboards, takes out dishes, checks the status of the formerly frozen vegetables in the saucepan on the stove and gossips about her love life. I duck under the long phone cord to get past her and go up the stairs to my room."