On Monday, two men - former Sinn Féin councillor Brendan McConville and 21-year-old John Paul Wootton - were handed respective minimum jail terms of 25 and 14 years after having been found guilty in March of murder.
"Although I'll never get Steve back, it means that I can move on. This trial was hanging over my head like a dark cloud and today I can move on from that," Kate Carroll told UTV's Jane Loughrey.
But despite her devastating loss, she insists she still feels no hatred towards the men who robbed her of her husband in an ambush in Craigavon in March 2009 - only pity.
The worst thing was to watch the people who had actually done the killing smirking - they had no remorse.
Describing the moment she first came face-to-face with the killers in court, she said: "I thought I would be hating them - I was afraid of feeling that I wanted to rush at them and slap them or something, but I just felt pity.
"I thought what a waste of two lives. I wanted to look at them and let them see they hadn't broken me."
Kate did hit out at the sentences handed down though, especially as the murder of a police officer carries a 30-year jail term in England.
"It should be the same everywhere - you can't make exceptions in one country. It's disgusting," she said, adding that she feared the lesser sentence handed to Wootton because of his age would not deter others from terrorism.
She also slammed comments made ahead of the sentencing by a defence barrister for the accused, who said that more police officers could have been killed but weren't.
"I think that was a disgusting thing to say, that he could have killed more - that's not showing remorse. It's okay to kill one cop, as long as you don't kill 20 or 30?" Kate said.
Wootton's mother Sharon was handed a 12-month prison sentence, but it was suspended for three years.
She had pleaded guilty during the trial to obstructing the police investigation into Constable Carroll's murder, by removing computer equipment from the home where she and her son both lived ahead of searches.
"The only thing I can say about Sharon Wootton is that she showed no remorse. I couldn't do it," Kate said.
"If it was my son, I would have him dragged by the neck down to the police."
But she admitted that she could find it in her heart to feel sorry for the parents of Brendan McConville.
"They seemed quite genuine. They looked at me a couple of times in the court and they nodded and I nodded back, because it's not their fault their son killed my husband," Kate said simply.
"I'm a mother, I have compassion - I thought bless them. I saw the hurt on their faces. I know what that's like."
Key to the trial proceedings was a witness for the prosecution known only as Witness M.
The man, who had been out walking his dog at the time of the fatal shooting, placed McConville at the scene - at the very point forensics had determined the gun had been fired from.
"The defence were trying to destroy him, to discredit him," Kate recalled.
"And I thought how brave, how courageous it was of him to continue with those people (the killers) actually looking at him. I was pleased that he had guts and the courage to stand up to them.
"That man has no identity anymore - his life's in ruins. But he'll have a fantastically clear conscience."
I wish I could meet Witness M because we are indebted as a family to him. We owe him everything.
While for Kate, questions still remain about her husband's death - including how it wasn't prevented, despite a military tracking device having been planted on John Paul Wootton's car - she is trying to look to the future.
Among her plans is the setting up of a trust fund in Stephen's name, working with children across all community divides in Northern Ireland to educate them about the impact of things like attacks on emergency services.
"If even one person can be deterred, ten lives could be saved," she said.
But thoughts of her own loss will never be far from her mind.
On the night he was killed, Constable Stephen Carroll was just two hours from the end of his shift. When the knock came at Kate's door, she thought he was home.
Instead two of his fellow officers had to break the news that he wouldn't be coming home ever again.
"It will haunt me for the rest of my life," Kate said.
"I think about it all the time - that he was just so close to home."