First of all do not despair. With Jesus on your side everything is possible.
Depression is quite common and treatable. It could be spiritual in nature, but it can also be caused by natural causes.
Get professional help to discard natural causes, if you still struggle with it maybe reading the following book might help you.
Title: The Noonday Devil: Acedia, the Unnamed Evil of Our Times
Author: Nault O.S.B., Dom Jean-Charles
It also gives ways to overcome depression, if other treatment option do not seem to work.
Last but not least, pray to Jesus for help, and when possible go to Church Adoration along with Sunday Mass unless there is a just reason not to attend.
Believe me, spending time with Jesus, transforms you for the better.