The Romanian woman who fell from London's Westminster Bridge into the River Thames during the terrorist attack was due to receive a marriage proposal later that day.
Footage of the atrocity appears to show Andreea Cristea, 29, falling from the bridge as the attacker ploughed a car through pedestrians.
She had been with her partner Andrei Burnaz, reportedly celebrating his birthday in London.
Speaking to the BBC, Romanian ambassador Dan Mihalache explained that he thought the car mounted the pavement and hit Mr Burnaz first, before pushing Ms Cristea into the Thames.
He added: "It is quite a dramatic story because they were two people that were tourists.
"They were coming to London to celebrate their birthday. He intended to ask her for marriage in the same day and this was unfortunately their destiny.
"It is quite a miracle that she could survive this very complicated experience because she was practically thrown to the Thames."
The ambassador said Miss Cristea was "stable, but in a good direction" after being operated on for a blood clot on her brain.