Peter Tatchell said he felt sorry for Iris Robinson's plight
Veteran gay rights campaigner Peter Tatchell has described Iris Robinson as a "hypocrite" for having an affair.
Mrs Robinson, a born-again Christian, caused controversy in 2008 for calling homosexuality "an abomination".
Mr Tatchell said although he was "sorry for the pain" Mrs Robinson has suffered, "she is sad and two-faced".
"Even now, she expresses no regret for her harsh, judgemental moralising against gay people. Iris seems as unforgiving as ever," he said.
Mrs Robinson said in a statement on Wednesday that she had attempted suicide after she had a "brief" relationship with another man.
She announced last month she was stepping down from politics due to ill health.
Mr Tatchell said it was "terrible that Iris Robinson has been driven to attempted suicide and a mental breakdown".
Iris Robinson's husband Peter is Northern Ireland's first minister
"I feel very sorry for her. But it is a great pity that this painful experience has not softened her heart towards the suffering of lesbians and gay men," he added.
Mrs Robinson caused a massive outcry in June 2008 for saying on a BBC radio programme that homosexuality was an "abomination" and that with help, gay people could be "turned around".
Her comments were made in the same week that a gay man had been badly beaten in a homophobic attack.
An online petition calling for Prime Minister Gordon Brown to reprimand Mrs Robinson gathered 16,000 signatures.
Amnesty International and the Labour Party were among the many groups calling for action against her.
Mrs Robinson, a member of the Metropolitan Tabernacle Church in Belfast, defended her remarks claiming she aired them in the wrong environment before saying "love the sinner, not the sin".
A police investigation examined claims her comments breached hate crime laws but no charges were brought.
Following the scandal, gay rights group Stonewall voted her the UK Bigot of the Year 2008 while the gay news service Pink News landed her with the nickname "wicked witch of the north".