Imposing a term of 11 years in jail, with an extended five year licence, Judge Simon Medland QC ruled that Aiden Moore, 23, of Morley Road, Lancaster, was a dangerous offender.
He said: "For a person of your age to have accrued these convictions and indulged in the behaviour which led to this case is a disturbing and very worrying factor.
"It is more or less conceded by your counsel that the court will conclude you are a dangerous offender.
"I have no hesitation in concluding you are an offender who poses a significant risk of serious harm by the commission of further specified offences.
Preston Crown Court heard Moore was already convicted of disturbing behaviour towards women.
On December 5 last year Moore sneaked into the pensioner's home as she waited for her pet dog to come back inside, then picked the frail woman up and threw her into her bathroom.
The victim has significant medical difficulties and lives alone.
Despite pain from her condition, she kept a "level head" and engaged him in conversation to try to gain details about his identity and ensure his DNA and other evidence was left at the scene, including a glass he drank from and cigarettes he had smoked.
Judge Medland added: " She is not as strong as she would want to be but the facts of this case demonstrates she is a woman of remarkable courage, resilience and fortitude."
Prosecuting, Barbara Webster said the victim told him she had problems with her legs and could not outrun him.
She added: " He told her he didn't want to hurt her but wanted to have sex with her."
"The defendant removed all his clothes and told her he loved her and she responded by telling him that was no way to behave.
The court heard she was determined to capture any DNA she could and even got a towel, before Moore removed her jeans and knickers and tried to attack her.
She told him she needed to get a drink, to which he agreed, and she sat down and suggested they had a cigarette to attempt to distract him.
But he told her: "I need you again."
Moore asked her for a packet of crisps but then he pushed her into the lounge.
His victim said: " If I let you do this, will you go and leave me alone."
He tried to attack her again then went to have a drink and a cigarette.
During the ordeal the victim noted his bad teeth.
The victim noted he was wearing an unusual Canada Goose jacket which he told her had cost £1,000.
When he eventually left but forgot vital evidence - his boxer shorts and mobile phone.
The woman pulled her door shut and called police at 8.48pm.
She was later taken to hospital to be examined and gave a " strong and detailed account" about her ordeal.
When officers arrested him at his home. Moore was abusive and had to be Pava sprayed.
Police retrieved his distinctive jacket, and asked his mother for his mobile number.
When they dialled it the phone left at the victim's home rang.
In a victim statement the woman described her medical issues.
She said: " My initial reaction was one of fear.
"I did not know what his intentions were but I knew I couldn't defend myself due to my mobility issues.
"Not only was I frightened for my own personal safety but of further breaks to my legs which would leave me with life changing injuries.
"I was also frightened he might hurt my dog.
"I realised the only way I could protect myself was to...try and play along with what he wanted."
She said she had been left numb, shaky, unable to concentrate, and exhausted from the "mental torture" and lack of sleep.
She added: " It's like a constant nightmare that I must relive."
"I hope his life moves forward and that he will accept the opportunities offered to him to change and to make a better future for himself."
His defence lawyer said : "He's sorry for what he's done. He understands the seriousness of what he's done.
"He appreciates the impact it must have had on her."
Judge Medland QC will order an indefinite SHPO and restraining order to be imposed on him at a later date, once the terms are agreed.
The Lancashire Post is more reliant than ever on you taking out a digital subscription to support our journalism. For unlimited access to Lancashire news and information online, you can subscribe here.