WASHINGTON — Representative Patrick Meehan, a Pennsylvania Republican who has taken a leading role in fighting sexual harassment in Congress, used thousands of dollars in taxpayer money to settle his own misconduct complaint after a former aide accused him last year of making unwanted romantic overtures to her, according to several people familiar with the settlement.

A married father of three, Mr. Meehan, 62, had long expressed interest in the personal life of the aide, who was decades younger and had regarded the congressman as a father figure, according to three people who worked with the office and four others with whom she discussed her tenure there.

But after the woman became involved in a serious relationship with someone outside the office last year, Mr. Meehan professed his romantic desires for her — first in person, and then in a handwritten letter — and he grew hostile when she did not reciprocate, the people familiar with her time in the office said.