McGreevey -- who proclaimed himself ''a gay American'' in 2004 while announcing his impending resignation as governor -- describes his long struggle with his homosexuality in the book The Confession.
According to the excerpts published Sunday in The Star-Ledger of Newark, McGreevey engaged in the secret encounters because he feared having a relationship with a man would ruin his chances of success as a politician.
''So, instead, I settled for the detached anonymity of bookstores and rest stops - a compromise, but one that was wholly unfulfilling and morally unsatisfactory,'' McGreevey wrote.
The excerpts do not mention whether the activities extended into his time as governor.
ReganBooks, a division of HarperCollins, is paying the 48-year-old McGreevey up to $500,000 for the 384-page memoir. He made an appearance Saturday at BookExpo America in Washington, D.C., where he told the newspaper his book is ``painfully honest.''
''A lot will resonate with readers,'' he said.
The excerpts do not detail his two marriages, or even the scandal, which became public knowledge during an August 2004 televised news conference in which McGreevey acknowledged a gay affair and said he would resign in coming months.
The excerpts also do not mention the former aide whom sources close to McGreevey have identified as the man he had an extramarital affair with.
According to the excerpts, McGreevey said he also became ``as avid a womanizer as anybody else on the New Jersey political scene.''
''I knew I would have to lie for the rest of my life - and I knew I was capable of it,'' McGreevey wrote. ``The knowledge gave me a feeling of terrible power.''
He said he became an avid student of human behavior during his rise from the state Parole Board to Woodbridge mayor to governor, and that allowed him to keep up the charade.
''I studied the moves, figured out what worked and what didn't, practiced and perfected my perfect inauthenticity,'' he wrote.