Hi
Andrewoder1999 and welcome to CF
I read that website and have to ask myself why do you not believe what was written there.
Depression is from the spirit of doubt and fear as only one themself can allow this spirit to enter into their mind as the mind is Satan's greatest playground.
I see you have checked that you are not a Christian, but I do believe you know who Jesus and God are, but have no personal Spiritual relationship with either one. If I am right about that then you need to humble yourself and bring all of this to Jesus and just sit and talk to Him in which is what prayer is all about. Pour your heart out to Jesus as you lay your burden down before Him. When you are done pouring it all out then be still long enough to hear His still small voice speak to you and to start a new work in you as Jesus brings the joy back to your heart.
We are here to help you and do not be afraid to ask questions in the Question forum. You are in my prayers