Yes Vertigo is a lifelong illness because there are no cures for Vertigo.
When someone has Vertigo they will most likely always have the Vertigo for the rest of their lives.
Treatments for the Vertigo can help ease the symptoms of the Vertigo but there's no full on cure for Vertigo.
My Grandma suffered from Vertigo for 30 years before she died and although treatments helped with her Vertigo she had the Vertigo for the rest of her life.
So in her case Vertigo was a lifelong illness.
Vertigo usually comes and goes and may come for a few days and then go away for a few days.
So you may not experience Vertigo everyday but it will come and go for the rest of your life.