Where do you live? Most people in most places don't behave this way.
Also - I won't labour the point too much about the health-related aspect of this, as I'm sure you've heard it before. Being that much overweight isn't good for you. It will make your life difficult in several ways, and as bad as it may seem already with how people treat you, that will probably be the least of your problems.
Obviously it effects your overall health. It can cause chronic joint problems. I imagine it costs more in terms of lifestyle (paying for two seats on a plane is the most obvious example I can think of). It is more restrictive - I imagine there are lots of things you can't do, or clothes you just can't wear. It almost certainly effects your chances of employment once you graduate university one day.
And also I think there is quite a real risk that our government/economy will 'run out' of money at some point, and when that happens, you won't be able to rely on the NHS anymore then for any sort of safety net or support systems.
I'm saying this to list all the other good reasons why you should try and do something about your weight, and to start today. Don't do it because of some drunk noobs. As I see it, people like this are often part of the problem. It can probably feel tempting (you've shown signs of this already) for you to retreat into yourself, not go out with people, which is more likely to cause depression (or worsen it), cause further over-eating, and exasperate your problems. Try to do the opposite instead.
Hope it goes well.