Gary Wells, 36, was said to be 'distraught' and struggling to cope when his eight-year relationship with Diane MacDonald ended three weeks ago.
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"He and Diane were like peas in a pod... I can’t believe he did this"
Miss MacDonald, the first woman train driver on the West Highland Line in Scotland, was powerless to prevent a collision when her ex-partner stepped on to the track in front of the train she was driving.
Mr Wells was killed instantly as he was hit by the train.
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Miss MacDonald was left so distressed that she required sedation after the tragedy, a school friend told the press.
The friend, who did not wish to be named, said: "Gary was a nice guy.
"He and Diane were like peas in a pod. They were together for eight or nine years and split up a few weeks ago. I can’t believe he did this. I heard Diane had to be sedated."
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"It’s so sad. He loved spending time with his son Lewis [his son from another relationship]. His weekends were devoted to him."
His family was too distressed yesterday to talk about what happened.
In a statement, Miss MacDonald said last night: "The circumstances are extremely upsetting for everyone involved.
"We would ask the media to please respect our privacy while we come to terms with what has happened."
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*Stock images used.