Something never achieved

"I left them to go to the lavatory, clear embroidered hand-towel, new soap, the bowl a frothy, disinfectant blue, a small bowl of potpourri; I noted and despised it all. On my quiet return I saw that, sitting a little apart, they had stretched their hands across the gap to each other, then, hearing my step, had quickly, almost guiltily drawn apart. That moment of delicacy, tact, perhaps even of pity, produced a second of conflicting emotions, experienced so faintly that they passed almost as soon as I recognized their nature. But I knew that what I had felt was envy and regret, not for something lost but for something never achieved."