The 25 year old Lithuania international was given his marching orders by referee Iain Brines for a headbutt on Dons match-winner Lee Miller but Hearts were convinced television footage would clear the player.
Brines reviewed the incident but decided to stand by his original call, condemning Zaliukas to a three-match ban.
"The club was very supportive of me, which I'm grateful for, and we were all confident justice would be done," he told Hearts News Today.
"I did nothing wrong. Okay, I made a mistake when I got my yellow card in the game and I admit that. Looking back, it happened in the heat of the moment but was something I shouldn't have done.
Zaliukas added: "I like football here but I am now disillusioned with the game.
"I enjoy Scottish football but now I'm thinking I would rather leave if this sort of thing is going to happen.
"I like Hearts and the fans and want to do well for the team but what chance do players have when this sort of thing happens?"