Alan Thompson says leaving Celtic in 2012 was "tough" as he faced difficulty both professionally and personally.
Thompson, now 46, was sacked as coach during Neil Lennon's first spell as manager after the pair had previously been team-mates at the club.
The former England midfielder subsequently coached at Birmingham, Blackpool and Bury.
"I was out of work and going through a divorce, which was tough," Thompson said of his Celtic exit.
"I wouldn't wish it on anyone. I was having a tough time personally and then it was tough after that. I've come through it now and looking forward to the future."
Thompson, who moved to Scotland as a player in 2000, scored 51 goals in 227 Celtic appearances and returned to the club as coach in 2010 after Lennon had been appointed manager.
Celtic won the Scottish Cup in 2011 and the Scottish Premier League in 2012 but Thompson then lost his post.
And though he admits not being on speaking terms with Lennon for a period, he insists there is now "no problem" between the pair, with Lennon now in his second spell as Celtic manager.
"Was there a period where we didn't speak? Yes," Thompson told the BBC's Scottish Football podcast. "He's got his reasons, I've got mine but absolutely no problem whatsoever now."
Thompson said he would "love" to return to Celtic as a coach some day, and said of Lennon's success in the dugout: "To have the influence he's had as a player and a manager, it's not surprising, knowing the character that he is.
"Who knows what happens next season? If they go and do the 10 [league titles in a row] he's up there with Jock Stein and Martin O'Neill in my eyes, but that's another nine or 10 months away.
"He's going to play a massive part in the season, even though he can't get on the pitch. Fingers crossed he can go on and get that magical 10."