Dalglish has walked out on the club before - in sensational style after a 4-4 draw with Everton in the FA Cup in 1991. He put the blame on pressure.
He also quit as Blackburn manager in 1995 after guiding the Lancastrians to the Premier League title.
But Spackman told the Sunday Mirror: "This is a different kind of pressure.
"Back then, he not only had to keep Liverpool at the top, where they had been for so long. That is demanding in itself. But Kenny also had to deal with the terrible emotional fall-out from the tragedies at Heysel and Hillsborough and that took an awful lot out of him.
"This time, it is different. I am certain he will not be walking away."