Since the election, Elon Musk had largely appeared inseparable from the president, helping to reshape government and root out fiscal waste.

As Mr. Musk entered President Trump’s orbit, his private life grew increasingly tumultuous and his drug use was more intense than previously known.

Steve Bannon has stoked the tension between Donald Trump and Elon Musk. The feud began when Musk pushed lawmakers to reject the president’s tax bill.

The two seem to have paused their online war of words. But the president may sell his Tesla and has continued to criticize Musk within his inner circle, according to those close to him.