It helped having his son, Exavier, now 2 years old, waiting for him.
"I went home to a son who was ready to play every time," Jackson said. "He had no clue if it was a good day, bad day. All he knew was Daddy was home and it's time to play, which definitely helps. Baseball is baseball. You kind of live a double life. You have a baseball life, and once you go home, it's the real world. That's the real job. It's not that this game is easy, but this is supposed to be the easy part of the day, your baseball life.
"I figured [the 2013 season] was one of those crazy years. I still took the field with confidence that I was going to win games, and it didn't happen that way. My worst season, I never lost 18 games. It happens. The only thing you do is bounce back and do what you know you can do."
The Cubs are counting on Jackson, 30, to rebound from an 8-18 season in which he led the National League in losses.
"I think it's hard to lose 18 games, honestly," he said. "It's one of those wacky, crazy years where sometimes anything that can happen does happen. How you handle it is in the eye of the beholder. I'm a firm believer in just keep fighting. As long as you have confidence and you know what you're capable of doing -- I know I'm not an 18-game losing pitcher. It happened. You just take it in stride and learn from it, and you get ready to come out and show what you can really do the next year."
Jackson did not hide in the offseason or do a lot of soul searching. After playing for his eighth big league team, and fourth in the last three years, the right-hander just shrugged it off.
"It's just a matter of going out and pitching like you know you can pitch," said Jackson, sitting outside the Cubs' new Spring Training complex. "It's about going out and doing what you're capable of doing. The season itself, that's when the soul searching is on. Once the offseason came, I didn't harp on what happened last year. As far as I was concerned, it was over."
This season marks only the fourth time in Jackson's 12-year career that he will be with the same team to open a second season. He pitched for the Dodgers from 2003-05, the Rays (originally the Devil Rays) from 2006-08, the Tigers in 2009, the D-backs and the White Sox in 2010, the White Sox and the Cardinals in 2011, and the Nationals in 2012. He signed a four-year, $52 million contract with the Cubs in January 2013.
Each time Jackson struggled last season, the contract was mentioned. This was his first multi-year deal. Did he put too much pressure on himself to perform?
"No," Jackson said firmly. "It's easy to make excuses and be like, 'Well, maybe he was trying to do too much,' or, 'Maybe someone was putting too much pressure on him.' I'm not a big believer in that.
"Had I come out and had a great season, no one would've said anything about the contract," he said. "It would've been a different outlook; it would've been, 'Now you have a contract, are you more comfortable? Is that why you had a better season?' You have a not so good season, it's just the opposite," he said. "'Were you putting too much pressure on yourself?'
"I just wasn't consistent in delivery, and it caused everything else to kind of just trickle down. I was victimized by my own self, trying to be a perfectionist, trying to be mechanical, instead of going out and doing what you do naturally."
Cubs catcher Welington Castillo said he never noticed Jackson stressing over his record or how the 2013 season went.
"He didn't change," Castillo said. "I talked to him a lot and said, 'Hey, don't think about it.' He said, 'What can I do? I tried and did all I can. I did all I can to win a game.' I like that part of him. Doing good, doing bad, he stays the same, has the same personality. He wants to learn and wants to do good. I understand at the same time, you do all you can, and sometimes you don't have good results."
Jackson arrived in Arizona early, eager to escape Atlanta's strange winter weather. On Thursday, the day pitchers and catchers reported to Cubs camp, he threw an easy side session with no one watching except his catcher.
Jackson does not feel he has to prove anything to critics, just his teammates.
"Everybody has a chip on their shoulder, but it's a positive chip," he said. "It's not a chip about, 'I have to show anybody anything.' You do it for your teammates; you do it for yourself and your teammates. These guys know what everybody is capable of before you bring them into the organization. Everybody knows what I'm capable of. It's just going out, having fun. You've got to have fun. You can't look at it as a job; you kind of have to look at it as a game and go out and play a kids' game and have fun doing it. That's when we all play to our best level, when we go out and have fun and we're competitive at the same time."
Jackson has not lost confidence after last season, one with a career high in losses, but not the worst in terms of ERA. He still made 31 starts, totaled 175 1/3 innings and struck out 135.
He says he's going to stay with what is comfortable.
"It's just a matter of getting one thing and sticking to it and go have fun," he said. "As far as confidence, as far as attitude, any of that, it didn't change last year. If you didn't know me, you wouldn't be able to tell I lost 18 games. You've got to stay even keel and have confidence in your abilities and what you know you can do."
On Oct. 29, the Jacksons welcomed a baby girl, Elan, into the family. Jackson calls her his "diva." Now, when Jackson returns home, he has two kids to play with. They don't care how Daddy did that day.
"If you had a bad day at the field, you don't want to play with your kids," Jackson said. "But you have a responsibility. You have a family. You have a responsibility to go play. My little man never knew good game or bad game; all he knew was Daddy's home. I look forward to 2014, ready to get everything started."