Germaine Lindsay's widow, Samantha Lewthwaite, of Aylesbury, has spoken of how her husband was a "peaceful man who loved people" until 2004, when they moved to Buckinghamshire from Huddersfield, West Yorkshire. He then began disappearing for days on end, visiting various mosques.
Sean Cassidy, whose son Ciaran was among Lindsay's 25 victims on the Piccadilly line train said he was unconvinced by her portrait of the bomber and said attempts to share the blame with others obscured the murder of innocent commuters.
Ms Lewthwaite, 21, described how Lindsay, who blew himself up between King's Cross and Russell Square stations in the worst of the suicide attacks, kissed their son Abdullah goodbye before leaving for his mission on the morning of the attacks.
"I feel sure he couldn't have gone through with it without seeing him one last time," she told The Sun.
"In the morning I found he'd left the keys on a table downstairs. He obviously had no more use for them."
She said she had assumed he was at a mosque on the day of the bombings and her "world collapsed" when police interviewed her and showed her CCTV footage of her husband.
Ms Lewthwaite, who gave birth to their daughter Ruqayyah this month, said she and her husband had been brought together through an interest in preventing attacks by Britain and the US in Afghanistan.
A mutual friend gave her Lindsay's e-mail address and they met at a Stop the War march in London, where she was studying at the School of African and Oriental Studies. Both were Muslim converts and they married in front of an imam at a friend's house.
"He was so angry when he saw Muslim civilians being killed on the streets of Iraq, Bosnia, Palestine and Israel and always said it was the innocents who suffered," she said. "Then he is responsible for doing the same thing but to his fellow British people."
Billy Chung For Yuen, the husband of another Piccadilly line victim, Rachelle Chung For Yuen, 27, said Ms Lewthwaite's story demonstrated a level of sympathy that jarred with the gravity of her husband's crime. "I've been out of the country for quite a time and have avoided these explanations but it probably does represent too much of an attempt to understand," he said .
Ms Lewthwaite's story of Lindsay's relatively recent conversion conflicts with evidence from Huddersfield, where he attended Rawthorpe High School. Lindsay's half-sister described a much earlier transformation after he converted to Islam at 15.
She said his conversion made him "isolated from all the world". He lost his interest in rap music and began telling friends to live a "clean" life, free of alcohol.
A key moment in his life appears to have been when he was 16 and his mother left Huddersfield for the United States to join a man she met on the internet. The leader of Kirklees Council in West Yorkshire told Channel 4 News that the community in which Lindsay was left alone and unsupported had been infiltrated by radical Islamists.
He said the local Omar mosque was particularly concerned about an Islamic bookshop above which Lindsay lived and the Huddersfield Dawa bookshop was blocked in its attempts to create an Islamic "learning centre" for fear that it might attract more extremists.
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