Why does Shukumar not look forward to the weekends when Shoba is home in the story, A Temporary Matter?

Shukumar does not look forward to weekends. Shukamar and Shoba avoid each other by staying on separate floors of their three-bedroom house. Shoba spends her time working. Shukumar does not play music in the house for fear of disturbing her. He thinks they will get over the baby's death.