The victim woke up to find David Horton, 47, assaulting her at a London hotel in 2018, Inner London Crown Court heard on Friday (July 23).
Earlier in the day, he had “laughed” when she had asked him to stop groping her.
Horton, a former construction boss, was convicted last month of four counts of sexual assault and one count of assault by penetration against the woman during the course of one day, which she said still gives her “flashbacks and nightmares” three years later.
On Friday, the court heard that the victim had been visiting London with her friend on May 19 and 20 2018 when Horton invited himself along.
Judge Usha Karu said Horton took the women to “various pubs and bars” around the capital and was caught on CCTV groping the victim’s bottom in a sushi bar.
The victim told him to stop as they left but he “laughed it off”, and when he told her he wanted to “**** her” she said “it’s not going to happen”, the court heard.
During a police interview following his arrest in June 2018, Horton admitted he “copped a feel” of her breasts in a taxi but denied all charges in court.
Judge Karu said he drank a “significant amount of alcohol” and racked up a bill of £400 on his own drinks alone.
Horton invited himself to the hotel where the women were staying and slept on the floor between their beds where he touched the victim’s thigh underneath her clothing.
Judge Karu said he assaulted the victim by penetration in her sleep, and when she woke up he put his fingers in her mouth.
Crying as she addressed the court, the victim, who cannot be named for legal reasons, said: “I feel disrespected and ultimately violated – the experience continues to haunt me on a daily basis.
“Too many people in small spaces gives me a panic attack, I continue to have flashbacks and nightmares.
“Since the assault I have not been able to maintain a long-term relationship, and I have not been able to share a bed.
“I have not been able to have a normal relationship with intimacy, touch and affection.
“It robs you of the ability to function properly… I returned to college after the assault but found it increasingly difficult to concentrate… I failed my exams and had to re-sit them.
“My house has been my prison and I have not been able to walk out of my front door, or be a mother, or a student without a feeling of anxiety.
“I feel like I am being held hostage by my deteriorating mental health.”
Judge Karu said Horton had mistaken the victim’s “openness” as “an invitation” for his advances.
“Her distress and anxiety have been plain to see,” she added.
“She describes how her life has changed and she now suffers with PTSD.
“She does not go out much, she keeps herself to herself. Her mental health has suffered enormously.
“She is unable to be the kind of mother she would like to be to her children. All this will take a long time to heal from, if at all.”
The judge told Horton he had “failed to accept your actions” and “shown no remorse”.
“You have lost your employment, your reputation, your comfortable lifestyle and of course your good character,” she said.
Defence lawyer Ravinder Saimbhi said that Horton, of Pembroke Street, Rotherham, South Yorkshire, will live with the consequences of his actions for “the rest of his life”.
She said: “He has not done anything like this before and his life is in tatters.
“The impact of that single day is going to stay with him for the rest of his life.”