She told The Observer newspaper: "I never even thought of the word widow. I thought I was a soldier. We were both fighting for freedom and justice and self-expression and he just fell in the battlefield.
"That is how I thought of it. That I had to keep going I saw that right away ... [I'm not concerned about old age], no. I feel good. Maybe it's because I don't think about the past so much. The past is so heavy. Part of me, of course, is still carrying it, but part of me is free from it."
In the past, Yoko has been accused of changing him when their relationship began four years before the end of The Beatles - but she has claimed she allowed him to be more comfortable.
She added: "[He gave me] an energy that said, 'It's all right to be me'. And that's what I gave him also.
"I didn't change him, as many people think, but he had a side of him that he was not able to express, because of the environment he was in, the people around him, his upbringing and all that.''