The ex-Rangers and Norwich City centre-forward was fined by the football association in August last year for betting offences, but his problem goes back a lot further.
He said: “About halfway through my contract with Rangers I didn’t have anything better to do after training than go to the bookies or sit online.
“Betting on football had been banned and, if anything, things got worse. I’d bet on horses instead. I knew absolutely nothing about horses. I still don’t have a clue. I open the app on my phone and go by the colour of the jersey or the name. If it’s a winner, it’s a winner; if it’s not, it’s not, and I move on to the next one.
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“It was every day on the horses and every single race. I was betting on anything; horses, dogs, virtual racing, roulette.”
Lafferty has been battling the problem in private but has since decided to go public. He credited Hearts and Northern Ireland coach Austin MacPhee for providing support, while also thanking owner Ann Budge, manager Craig Levein and national team boss Michael O’Neill for backing him.
“I feel lucky to be at Hearts with so many supportive people around me. Austin, Craig, Ann - what they’ve done for me makes me feel stronger this time.
“Michael (O’Neill) has been brilliant as well. It’s funny, I used to hate playing at Tynecastle when I was with Rangers. The fans were on top of you and there was so many of them.
“I’m glad we’re on the same side now. I want to show them that I’m here to sort my career and my life out. If I don’t go to meetings I know Austin will be on the phone and Craig will probably slap me across the head. I’ve got to sort this out.”
Hearts have since released a statement giving “total support” for the player.
It read: “Kyle took the enormously brave step of coming to the club and asking for help. No one should underestimate how difficult that decision was for him and his family. However, as is well recognised, the first step to dealing with a problem of this nature is to acknowledge that the problem exists. He has earned our great respect for doing so.
“Kyle has the total backing of the coaching staff and his teammates as he deals with this challenge. It is a testament to the great footballer and character he is, that he has in no way allowed his personal battle to affect his performance on the training ground or on the football field. For the avoidance of doubt, Kyle will continue to train and play as normal.”