Suk Yin Cheng, 20, died when she was struck by the HGV and suffered multiple injuries on a busy dual carriageway.
The inquest into her death, which was held at Burton Town Hall, heard how she was terrified her boyfriend of two years, Kahil Mohammad, 22, was going to be forced to marry someone else.
She left a note expressing her concerns about losing him on her iPad and even told friends on social media.
The inquest heard Mr Mohammad told police he and Ms Cheng were “inseparable” and he wanted to marry her.
He also told officers an arranged marriage had not been discussed on the evening before her death.
Ms Cheng died in the early hours of July 2 last year after being hit by the lorry on the A38 at Clay Mills near Burton-upon-Trent, Staffordshire.
The night before she died, she had been at work at the Boots warehouse in Burton, before driving to Mr Mohammad’s house in Derby.
He told police they had chatted and “she seemed fine, happy and smiling” when she set off at 11.30pm.
She was then due to drive to her parents home in Oakwood but instead drove back towards Burton on the A38 where she pulled into a layby.
Just 30 minutes before her death, the inquest heard she called Mr Mohammad and told him: “I love you, I’m doing this for you.”
In his witness statement, Mr Mohammad said he had spoken to Ms Cheng at 12.15am on July 2.
He said: “She said that she loved me and that she was doing this for me. I did not know why she was saying that.”
The inquest heard Ms Cheng then died at 12.40am when she was hit by the lorry on the A38 at Clay Mills near Burton.
Staffordshire South Senior Coroner Andrew Haigh ruled that Ms Cheng had “committed suicide while distressed” at the inquest yesterday.
He said: “Having heard the evidence, I am satisfied that the loss of Mr Mohammad to an arranged marriage to someone else was an ongoing concern to Caley.
“In a distressed state, she has deliberately walked out in front of a heavy goods vehicle with the intention of killing herself and she has done so.”
The inquest heard Ms Cheng did not have any diagnosed physical or mental health problems and was not intoxicated when she died.
PC Carl Matthew, from Staffordshire Police, said her phone showed she had spoken to friends about her concerns over an arranged marriage between Mr Mohammad and another woman.
After the hearing, her family described her as “optimist” and said she dreamed of becoming a fashion designer but had taken a year out to experience the world of work.
Her uncle, Michael Cheng, 48, said: “Caley was a warm-hearted person and a family girl. She had a good sense of fashion and was a positive girl and an optimist.
“It is still very hard to believe she would do this in this way as it is so unlike her.
“Everyone from the family will remember her and love her always.”
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