Hi Pinwheel. You are not alone here, and all the replies you got are proof of it.
As @dawgofdawgness said, dont blame yourself about having depression.
Having depression is Not your fault just like a concrete block randomly falling over a person is not that person`s fault.
Also, as @Jenny-Toons said. If you are not getting help, i would also recommend you getting professional help. Don`t be ashamed about getting into therapy. We are humans, is okay to ask for help when needed.
Overcoming depression takes time and therapy, but is completely possible. There is a calm after the storm.
In these links there are lots of advice from people who had some experience with depression.
Wish you the best Pinwheel and hope this helps. If at least one of these things helped you at least a bit, it was completely worth it.