Thatcher returned to the backbenches as a constituency parliamentarian after leaving the premiership. Aged 66, she retired from the House at the 1992 general election, saying that leaving the Commons would allow her more freedom to speak her mind.
In the 1992 general election May stood unsuccessfully for the safe Labour seat of North West Durham, placing second to incumbent MP Hilary Armstrong by 12,747 votes (27.6%) to 26,734 (57.8%), with future Liberal Democrat leader Tim Farron placing third.
Their marriage was increasingly strained as he learned of her affair with Dali Mpofu, but he supported her during her trial for kidnapping and assault. He gained funding for her defence from the International Defence and Aid Fund for Southern Africa and from Libyan leader Muammar Gaddafi, but in June 1991 she was found guilty and sentenced to six years in prison, reduced to two on appeal. On 13 April 1992, Mandela publicly announced his separation from Winnie.
In April 1992, McCandless hitchhiked from Carthage, South Dakota, to Fairbanks, Alaska. As noted by Krakauer, McCandless was last seen alive at the head of the Stampede Trail on April 28, 1992, by a local electrician named Jim Gallien. Gallien had given McCandless a ride from Fairbanks to the start of the rugged track just outside the small town of Healy. Gallien later said he had been seriously concerned about the safety of McCandless (who introduced himself as "Alex"), after noticing McCandless' light pack, minimal equipment, meager rations, and obvious lack of experience. Gallien said he had deep doubts about "Alex's” ability to survive the harsh and unforgiving Alaskan bush.