The sports star hadn't planned to ask his girlfriend to marry him when they set out on a boat trip, but the opportunity was too great to miss when the vessel ran out of gas.
He recalls, "We were in Sun Valley, Idaho, which is a good place. We're on this lake and these people let us go out to their lake cabin and we took this boat out to the middle of the lake this is one of those little fishing boats with the motor behind.
"It ran out of gas in the middle of the lake, so I thought, 'You know, we're stuck here, I may as well ask her now.'
"I felt bad (because) I didn't have the ring with me but it was too perfect, too beautiful."
Crow admits she was stunned by the proposal, but didn't hesitate to say yes.
Speaking on yesterday's (20SEP05) OPRAH show in America, she revealed, "He definitely pulled out all the stops... He was being really romantic."
Crow insists she'd be foolish to turn down the chance to marry Armstrong: "There are too many things to name that I love about him - he's gorgeous and he's funny and he's smart and he's a fantastic dad. Gosh, I just love him."
The couple plan to wed next spring (06).