I was in the same boat. After 12th,my parents moved cities. I also did engineering like a typical Indian student. But my first year engineering was brutal. I don't think I could adjust to it. I failed 3 papers from my first year - I really didn't have any aptitude for chemistry or computer science and they were the papers I failed along with electronics. And then persisted with clearing them. But then the incident depressed me and I stopped going to classes in second year.

I dropped out, got really fat and isolated. The only saving grace was my high marks in maths. I switched. And then did really well. Got my Masters and PhD. After employment was when I started running and weights., I lost weight. Friends I'm slowly building up. But socially, on average I've fewer friends.

So listen to what Sandy said - don't go in a hole. Stay socially active. Also do something else if you're not interested in commerce. But it has to be promising career wise. You also need to put the hard yards in. Join social clubs - sports, debating societies etc.

Do hard work in your career. Even if you're lonely or fat, being in a stimulating career can take away some of that depression.