What most people cannot comprehend, for some very bizarre reason, is that many chronic problems do not have one-time solutions. They require chronic solutions.
Take alcoholism. The "cure" for alcoholism is never drinking. You never stop being an alcoholic, you can only manage it by not drinking.
Take obesity. Obesity has no "cure" either in that sense. The "cure" for obesity is diet and exercise management, forever, until the day you die. It's like taking a pill, every day, forever, until you die. If you one day decide to stop taking the pill of diet and exercise, you will be obese again. In that sense, the obesity never left you, merely it's symptoms left you temporarily while you managed it.
Mental health is the same way. There is no magic "oh now I'll never be sad or anxious again!". No. You manage it every day, forever, until the day you die. You manage it via therapy, behavior modification, and medication. If you stop doing that, it will come back, because it never left you. It's a chronic condition, like being a brunette.