Jake Anderson, 15, was walking his girlfriend home from school when he got involved in an argument with another boy – and almost paid with his life.
Dale Warburton, 17, lunged at Jake at a bus stop and knifed him in the back and side, puncturing his lung.
The attack only stopped thanks to the 'considerable bravery' of two boys who stepped in and grabbed the knife.
Details of the stabbing emerged as Warburton was jailed for six years after he admitted wounding with intent to cause grievous bodily harm and possession of an offensive weapon.
The court was told Jake, who was initially treated for his injuries by the mother of his girlfriend Katy Singleton before being rushed to hospital, has now made a full recovery.
Jake, now 16, said after the case: "I was so scared at the time - it was the most terrifying thing that has ever happened to me.
"If it wasn't for Katy's mum I don't know what would have happened. She knew what to do. She wrapped a towel round my chest really tight to stop the bleeding. I kept asking her if I was going to die.
"I can't find the words to explain how angry I feel towards Dale Warburton. I have had anger problems, stress, my confidence has gone down and I couldn't concentrate in my exams."
Preston Crown Court was told the incident occurred at 3.30pm on January 10 after Jake met up with 16-year-old Katy upon leaving Ashton Community Science College.
On their way home he spotted Warburton waiting at a bus stop close to Our Lady's Catholic High School and decided to confront him about the text messages.
Warburton tried to board a bus but when the doors did not open he lunged at Jake and stabbed him, the hearing was told.
Several other schoolchildren were in the area at the time of the attack, the court heard, which only stopped when two other teenagers, Ryan Hurst and Ryan Clegg, stepped in and overpowered Warburton.
Jake was taken to Katy's house where his mother, who is a nurse, stemmed the bleeding from his wounds and dialled 999. He then spent two days being treated at Preston Royal Hospital before being discharged.
Warburton, from Ingol, Preston was initially charged with the more serious charge of attempted murder, but his guilty plea to grievous bodily harm was accepted.
He was told that he must serve at least two thirds of his sentence and will be on licence for an extra five years upon his release. He was given an indefinite restraining order, banning him from contacting the victim.
Passing sentence Judge Anthony Russell QC, told Warburton: "You have shown yourself to be a dangerous young man.
"Although you claim to have changed since your arrest and detention in custody, given the nature of this case and your history I consider public safety to be an important consideration in this case.
"Your actions in attacking him in the way that you did was out of all proportion to any threat you could have perceived from him and the fact that you had the knife with you is an indication you were looking for trouble. The evidence shows you completely lost your self-control."
Jake's father Craig, said: "It has been terrible. You get the phone call you dread and they are saying, 'your son's been stabbed and rushed to hospital'.
"Now it is all over I'm just really happy about the sentence."
In a message on Facebook Katy said: "At last he's been sentenced and no-one's got to worry anymore. He's got what he deserves and I hope something happens to him. I love you Jake."