Do you think it's bad that I want all the mentally ill people in my environment gone?
That seems extreme. Is there anyone you know with a mental illness?
No, but I've learned about them, and I know that they don't deserve my respect.
You should not think that mental illness is bad. You probably do know someone with one, they just mask it well. That doesn't make them any less of a person.
I can't stand being around them, though.
I think you're being extremely callous and judgmental. Just because someone is dealing with mental illness doesn't make them bad, and certainly doesn't mean that you can act like you're above them. You should try to be more accepting of people.