The American who swam to see Aung San Suu Kyi is a Vietnam veteran who suffers from post-traumatic stress disorder, according to his ex-wife.

Yvonne Yettaw, the mother of six children with John Yettaw, said that her ex-husband received a disability pension from the US Department of Veterans’ Affairs because of his illness.

“You can’t raise your voice. You cannot touch him without startling him. I lived with the man. Yes, he has it,” she told The Times. “He also has bipolar but I don’t believe he has been diagnosed with that. I would call him that. He gets an idea. He goes and does it and gets in trouble,” she said.

Relatives said that Mr Yettaw, a former building contractor who has not worked full-time for 20 years, spent months in Asia last year with his teenage son Brian and visited Burma. He left his home in rural Missouri about three weeks ago to return to Asia, telling his family that he was working on a book and searching for Americans listed as missing in action during the Vietnam War.

Yvonne Yettaw had her own explanation for why he had swum across a lake to see the Nobel Peace Prize laureate. “He just wanted to talk to the lady,” she said.

Mr Yettaw, 53, who is white but has some Native American ancestry, has suffered a number of misfortunes in his life — including a fire that destroyed his family home and the death of a son in a motorcycle crash. He often complained to relatives that his mother was schizophrenic and mistreated him and his sister Debbie.

“He had a terrible past. His mother was schizophrenic and she would not take care of them . . . It’s bugged him all his life,” Doris Brochu, Mrs Yettaw’s mother, said.

“He has got some serious problems. I think he has some mental problems,” she said. “He can be very nice. He is very well spoken and educated, but he has a bad side to him. He has a good side and a bad side.”

Mr Yettaw met his future wife while working as a building contractor in southern California. About 20 years ago the couple moved to a part of Missouri where Mr Yettaw’s father had land and started a family. They had six children including Clint, who died in the motorcycle crash two years ago at the age of 17.

Craig Dehner, Mrs Yettaw’s son from a previous marriage, said yesterday that Mr Yettaw blamed himself for Clint’s death. “I read an e-mail he has sent my other brother. He said: ‘Since Clint’s death, I’ve felt like a failure.’ He let Clint do what he wanted. He probably felt responsible because he let him have a motorcycle.”

Mr Yettaw and his family lived in a mobile home on 160 acres of unfarmed land outside Falcon, Missouri. He became involved with the Mormon church in the nearby town of Lebanon.

For many years, Mr Yettaw received a small disability pension from the US Government, according to his former mother-in-law. But he also received college grants to study to be a doctor. “He has never held a job,” Mrs Brochu said. “He has always been in school. It was school grant, school grant, school grant.”

Just over two years ago, Mr Yettaw did have some good fortune when he won a claim for a 100 per cent disability pension from the US Government. Flush with the money, he paid off a car loan for his ex-wife. They divorced about five years ago and he has since remarried.

Mr Yettaw, who is diabetic, took his son Brian, now 17, to Asia for three months last year, removing him from school. Relatives said that the two went to Burma and Mr Yettaw also planned to visit Iran and Iraq.

Mrs Brochu said: “He told me he was going to Iraq. I told him: ‘You’re not taking my grandson over there.’ He said ‘no’.

“He said he was writing a book. He said he was looking for Americans who went missing in action. He was trying to do a thesis. I was very upset because he has left his kids just strewn all over the place.”

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