Steven Monjeza leaves Tiwonge Chimbalanga for a woman a week after the couple were freed from jail in Malawi

They became an international cause celebre after being sentenced to 14 years in prison under Malawi's draconian laws against homosexuality.

But today the story of Steven Monjeza and Tiwonge Chimbalanga, the first same sex couple to seek marriage in Malawi, took a further twist when it emerged that they had separated and one of the men now has a female partner.

Outrage over their convictions for gross indecency and unnatural acts last month gave way to relief when the country's president, Bingu wa Mutharika, freed them on "humanitarian grounds".

Their separation was called as a "tragedy" by one campaigner who blamed it on homophobic threats and abuse. Monjeza, 26, has begun a relationship with Dorothy Gulo, a 24-year-old from Blantyre.

Monjeza, who faced family hostility towards his previous relationship with Chimbalanga, said he no longer wanted to be associated with homosexuality.

"I have had enough," he said. "I was forced into the whole drama and I regret the whole episode. I want to live a normal life ... not a life where I would be watched by everyone, booed and teased."

Chimbalanga, 20, said Monjeza had found a female lover "to hurt" him. "But I am not worried. You cannot force love, and nobody forced him when we did our symbolic wedding in December."

He insisted that he did not resent Monjeza's decision. "I will also marry because there are lots of good men around. I will remain a gay," he told the Guardian.

Monjeza, who lives in Kameza, a village six miles from Blantyre, has been pressurised by relatives to leave and seek a heterosexual relationship instead. His uncle, Khuliwa Dennis Monjeza, has expressed determination to prevent the two men reuniting. Others warned Chimbalanga not to set foot in the village, threatening that they would "deal with him".

George Thindwa, director of a local human rights group, said he saw the split coming. "Monjeza was always a reluctant person in this partnership, but they managed to get the waters tested and they have seen the waters are rough," he said.

The former political prisoner, who represents the Association for Secular Humanism, said it was now up to other gay men and women – who largely keep their sexuality private for fear of stigma and imprisonment – to pick up the baton and fight for their rights. "Malawi will never be the same on the gay issue," he said. "The couple have opened a can of worms."

Others paid tribute to the men's courage. Peter Tatchell, of the gay rights group Outrage!, said: "It is a tragedy that homophobic threats and abuse have forced this couple apart. They were deeply in love. The pressure has got to Steven. Very understandably, he wants a quiet, safe life. This would not be possible if he remained with Tiwonge. They would both be at risk of violent attack."

Tatchell, who was in communication with the couple for more than four months via prison visitors he arranged, added: "Tiwonge and Steven never set out to be political, but they have done more for gay and transgender rights in Malawi than anyone else.

"I salute them. They are lions of Africa. They have helped continue the unfinished African liberation struggle by seeking freedom for gay, bisexual and transgender Africans."