At an emotional evening news conference immediately after he was removed as speaker of the House, Representative Kevin McCarthy gave an inconclusive answer about whether he would remain in Congress. “I’ll look at that,” he said then.

Over the past two months, Mr. McCarthy has given the life of a rank-and-file member a hard look and discovered it to be a painful existence after having been at the pinnacle of his party in the House for more than a decade.

These days, Mr. McCarthy, famous for his preternaturally sunny California disposition, has been hard to cheer up. He no longer attends the conference meetings he used to preside over, and at times has struggled to contain his anger at the Republicans who deposed him. (He denied the accusation from one of them, Representative Tim Burchett of Tennessee, that he elbowed him in the kidney in a basement hallway of the Capitol.)

He has also struggled to make peace with the idea that it’s time to go, even as California’s Dec. 8 filing deadline to run for re-election draws near and his colleagues expect him to leave. “When you spend two decades building something, it’s difficult to end that chapter,” said Representative Patrick McHenry of North Carolina, one of Mr. McCarthy’s closest friends in Congress. “His life has been building the Republican majority and attaining the third-highest office in the land. It is difficult for any mortal to deal with an abrupt end and determine his next chapter.”