I keep up a lie and tell people my parents are dead instead of the truth: that I cut all contact with them because they're awful
That's unfortunate. Why did you decide to cut contact with your parents?
They lectured me too much and I was so tired of it
It's bad to lie about your parents being dead, imagine the consequence of someone you care about finding out that your parents are still alive. Instead you should be honest about the type of relationship that you have with your parents.
I guess you're right but I don't care.
Don't you want to think of what could happen, or what people could think of you if this secret was revealed? I believe you should still respect your parents and just say you aren't on good terms with them. Everyone will understand because family problems are common.