"It is at least a small comfort to me, as a gay rights and marriage equality advocate, to know that like any marriage, gay and lesbian couples are subject to the same complications and hardships that afflict marriages between heterosexual couples," Robinson wrote. "All of us sincerely intend, when we take our wedding vows, to live up to the ideal of 'til death do us part. But not all of us are able to see this through until death indeed parts us."
Robinson did not respond Sunday to email and phone requests for comment from The Associated Press.
Robinson has never been fully accepted within the more than 70 million-member Anglican Communion, which is rooted in the Church of England and represented in the United States by the Episcopal Church.
The bishop endured death threats during his 2003 consecration and intense scrutiny of his personal life, and in 2006, he sought treatment for alcoholism. His election prompted some Episcopal dioceses and parishes to break away and establish the Anglican Church in North America with other theological conservatives overseas. Robinson was barred in 2008 by then-Archbishop of Canterbury Rowan Williams from the Lambeth Conference, the once-a-decade global meeting of all Anglican bishops, as Williams struggled to find a way to keep Anglicans united.
But Robinson was also widely celebrated as a pioneer for gay rights, became an advocate for gay marriage and was the subject of several books and a documentary about Christianity, the Bible and same-sex relationships. He delivered the benediction at the opening 2009 inaugural event for President Barack Obama and, after retirement, became a senior fellow at the Center for American Progress, a Democratic think tank with close ties to the White House.
Robinson, 66, had been married to a woman and had two children before he and his wife divorced. He and Andrew had been partners for more than a decade when Robinson was elected to lead the New Hampshire Diocese. The two men were joined in a 2008 civil union in New Hampshire, which became a legal marriage when the state recognized gay marriage two years later.
"My belief in marriage is undiminished by the reality of divorcing someone I have loved for a very long time, and will continue to love even as we separate," Robinson wrote. "Love can endure, even if a marriage cannot."
A spokeswoman for Episcopal Presiding Bishop Katharine Jefferts Schori referred requests for comment to the Diocese of New Hampshire. A spokeswoman for current New Hampshire Bishop Rob Hirschfeld cited an email he sent to local clergy and wardens urging prayer for Robinson and Andrew.
Robert Lundy, a spokesman for the American Anglican Council, a fellowship for theological conservatives, said the argument against gay marriage is based on the Bible and will not be helped or hurt by the dissolution of any one marriage.
"The teaching of the Bible and the Anglican Communion is very clear that marriage is the union of one man and one woman for life," Lundy said in a phone interview.
The Rev. Susan Russell, an Episcopal gay rights leader in the Diocese of Los Angeles who preached at Robinson and Andrew's union, said the end of the men's marriage was tragic, but Robinson would remain an "icon of a faithful Christian man living out his vocation, not by his choice, but by his placement in history."
"Of course, he'll get some slings and arrows," Russell said in a phone interview. "But the paradigm has shifted so dramatically that people more and more get that our marriages are no different than anyone else's marriages, and that includes the reality that some of them fail, no matter our dreams and hopes."