Is it considered a sin to turn off one's phone and distance oneself from one's mother for a day or two when feeling distressed by her, or during fasting, to avoid inappropriate speech or conversations that the questioner does not desire, knowing that she does not need him during those periods?

It is permissible to turn off the phone and be alone away from the mother for some time, as long as it does not cause her harm. However, addressing her in a way that angers her, or offending her verbally or physically, is not permissible due to the great right of the mother. Allah has commanded that parents be addressed with politeness, gentleness, humility, and reverence, and has forbidden scolding them or speaking harshly to them. Allah Almighty says: "So do not say to them, 'uff,' and do not repel them but speak to them a noble word. And lower to them the wing of humility out of mercy and say, 'My Lord, have mercy upon them as they nurtured me when I was small.'" The noble word is the soft, gentle word, such as saying: "O my father," and "O my mother." One must strive and seek Allah's help to be patient and have good manners in general, and with the mother in particular, as good manners are acquired through habituation and practice.