From Goodreads:

When Thomas Hobart boards a train and heads west to attend college in Chicago, he leaves behind a world of unspoken feeling. On the train he meets Dennis, a conductor, and every Thursday evening for the next year they meet in a downtown hotel for a series of passionate, next-to-wordless encounters. "Love without lust, lust without love" becomes Thomas's motto, and, true to it, he keeps his liaisons with Dennis a secret from his newfound college friends Michael and Jane. When Dennis ventures to break the pattern of their affair and enter Thomas's world, their relationship fails. But everything Thomas has come to believe in is called into question when he visits New York City and meets Stuart, a handsome, enigmatic painter. Thomas quickly becomes immersed in Stuart's artistic life, and just as quickly becomes lost in the complications of love. Not until his own life has fallen apart does Thomas begin to locate the sources of his feelings, to recognize his need to join love and sex, desire and obligation, carnal satisfaction and emotional fulfillment.