The way that you've used two stanzas to contrast happiness and depression is a powerful way to approach the topic, and I think you have something that can become an incredible poem. The framework is already done. Now it's time for the cleanup.
The biggest issue with this poem is the use of cliche language. Depression has been called a dark shadow more times than I can count, so it's important that you find another way to frame it. The same goes for the phrase "crushes my spirit." The second stanza's use of spirit twice is underwhelming and also needs to be addressed. There's obviously a christian theme under this piece, so I think there's a simple fix.
Use pieces of the bible to describe depression and joy. Obviously, depression will include darker references (rapture, judgement, plague, etc) and joy will be positive (miracle, rewards of faith, etc). For example
depression--
the trumpet that crumbles me like the walls of Jericho
joy--
the healing touch...
Obviously you can do better, but these examples should get my point across. If you're going to write poetry influenced by the Bible, use it to your full advantage. The Bible is easily one of the most familiar books, and many of the metaphors can be used here to your advantage.
Hope this helps!
Thank you for your detailed input!