You're not alone out there, man. There is a lot of people that feels the same and I can relate. It builds day after day and it is hard to track it back to anything originating it, but it is real.
Many things work for me when depression come. It is important to keep the body and mind busy and in general hitting the gym as much as you can works. Little success and achieved objectives build self-esteem so if you cannot read 4 books a month, reduce your objective to 3, 2, or 1 in order to achieve it. Regarding the job seek, just go for interviews and believe you can make it. Good luck!