you need to foucs on your finals for only 30 minutes a day read the texbook understand the content and make fast little notes. You can do this it may be hard but just 30 minutes a day will help a lot. depression is difficult you cant see or do anything clealy trust me i know i still suffer from it. You are not a failure even if you messed up everyone messes up you are doing incredible you are sufferning from a sever mental illness and you stiil want to well.
Believe in yourself it may be impossible but you'll make it.