Non Stop Flight by Roy Debussy; Jay Arpage

'Eric Leighton discovers his wife dallying with a lesbian, so he beats up and rapes the lesbian (juicily described) whereupon his wife commits suicide. Then Eric gets involved with Celia, a stereotype “dish” with an ineffectual husband; when Celia tires of him he beats her up and rapes her (juicily described) then runs across the lesbian who has seduced his wife and Celia, so he beats her up and rapes her again (juicily described) after which Eric and the lesbian get married and live very happily forever after.' - Marion Zimmer Bradley