It's a mental state that needs to be improved, depression isn't a disease it's a mental health condition. A disease is something that must be treated with medication but you'll always have it, mental health is something that can improve or degrade based on your current state of mind. You need to pick yourself up and give yourself a new focus, try joining a local class or group, doing something that's interested you for a long time but you've never pursued, having new things to do and new people to interact with can break the cycle really easily. Also good diet and exercise can help, mental and physical health are linked after all. Being down isn't the end, it's the start of the climb but nobody will carry you.