I told someone a lie about my dad once.
Why did you tell a lie about your dad?
I told them that my dad has cancer. I just wanted to get their sympathy
That's horrible, but at least you feel bad about it. Lying is wrong and you should avoid doing it in the future.
Yeah I feel bad about it. I just don't know how to deal with being caught out and how people react to it.
Well, you could always tell them the truth. I am sure that they will be less upset if they hear the truth directly from you.