The September episode with the process server in their driveway was perhaps the most dramatic example of Ms. Paxton’s acting to assist her embattled husband, who by that point was facing not only political opposition on the abortion issue, but also criminal indictment for securities fraud and a federal investigation into his firing of top aides who had accused him of corruption. But it was far from the only time she had done so.

In 2019, months after taking office, Ms. Paxton introduced one of her first pieces of legislation: a bill to change the law regarding investment advice that her husband had been accused of violating. The proposal went nowhere.

“No one should think of Angela Paxton as the scorned wife here,” said Matt Angle, the director of the Lone Star Project, a Democratic political organization. “She’s a full partner.”

On Jan. 6, 2021, Ms. Paxton stood on stage next to her husband during a rally with President Donald J. Trump near the U.S. Capitol as he listed his efforts to challenge the results of the 2020 election in several states, hoping to overturn them.

By that point, many of the accusations against Mr. Paxton, including the affair, were already largely known. “Thank God for a Legislature in Texas, like my senator, Angela Paxton, my wife, who put in place laws that protect against fraud,” Mr. Paxton told the crowd in Washington that day, as she nodded beside him. As they walked from the stage, she gave him a quick kiss.

And she was with him smiling at his swearing-in for a third term this year.

“They’re not hating on each other,” said Pastor Ellis, who said he offered an official prayer during the swearing-in ceremony. “If she were trying to make a statement, that would be a pretty easy way to make one,” by not showing up, he said. “I have yet to meet a Christian couple that does not have challenges, and the fact that they’re still together should tell everybody something.”

Susan C. Beachy contributed research.