The Blink-182 drummer was on a private plane that crashed in 2008, killing four people.
The 45-year-old escaped with critical injuries alongside his friend Adam Goldstein, better known as DJ AM.
The American musician made his first plane journey since the tragedy with a flight to Mexico with his reality star girlfriend on Tuesday.
Sharing a picture on Instagram of the couple embracing beside a private jet, he wrote: “With you anything is possible.”
Kourtney also shared the post on her Instagram Story and said: “Anything and everything with you.”
Her famous sisters commented on Barker’s picture, with Kim Kardashian West writing: “THE CUTEST EVER.”
Meanwhile Khloe Kardashian wrote “Love conquers ALL”, adding: “I’m going to cry.”
The drummer was almost killed in the plane crash in South Carolina and was left in so much pain from burns that he offered friends one million dollars to help him end his life.
He and Kourtney made their relationship Instagram official in February.