We have to train ourselves to be Muslims. You are going through that. In my immediate environment there is a person who lapses into Gheebah at the earliest opportunity. One day few of us were sitting on a big table and some one one said some thing that was Gheebah of this person. Obviously he was not there. I just got up from my chair and sat on a different chair. The effect was a bit dramatic - everybody else too got up from the table. Clearly all of us were inherently aware that we were going to indulge in the same sin of which we have been accusing that person. This is the subtle Ahsaas that we have to clutch firmly if we want to protect our iman.