As someone who was in OP's shoes literally, ( my 1st job was a 4 month contract with an option to extend, which never happened) you tend to shut out people. It just happens. I can't explain it why but it does. I consider myself as a social person who can't live without friends, but i ended up just sitting in my room. When i graduated and while i was working i could never imagine me not going to gym but guess what, i hated going to gym. Heck i stopped going to gym even though i was sitting at home all day. I can't explain why it happens but it does.

Have you ever tried to seek help when you were depressed? This can be very depressing by itself.

You should read this article and discussion. https://news.ycombinator.com/item?id=13164925

"Sane Thinking about Mental Health Issues" - it discusses the phenomenon where in some cultures 'getting professional help' before reaching out to friends or family is absolutely necessary, and that 'abnormal' mental health related feelings should not be shared or discussed.

Your comment reminded me of that attitude. Maybe it would be enlightening for you to read about other perspectives

But in order to seek help, I have to talk