I faked having a dead twin sister from ages 11 to 13
What made you fake having a dead twin?
I liked the attention that I got from it.
That's a pretty big lie, pretending to have a twin that died. I'm sure the attention was fun, but it's too big a thing to lie about. Once you lie, people may not believe what you tell them in the future.
Why do I have to tell the truth?
Because people would be upset if you lie to them and being caught in a lie is awkward. People also won't trust you anymore.