Salam alikom
I just red about depression
It is so bad just like you said and any one could experience it for many reasons
Yes everyone is vulrnerable to mistakes and problems but as you said people should not blame themselves for things happened especially if they can not change it
The solution is to accept it and try to fix it, if nof take it as a lesson and move forward for their lives
Thank Allah for your recover
And May Allah keep you in the right path
Look at this link i found it while searching about depression through google
(the article is in arabic)
https://www.alukah.net/social/0/295/