I just treat mine as thought it's money I never had. It's nice to be paying back all capital at the moment, but during the 5% interest years I was paying back less then the interest payments, so my debt was actually increasing.
I felt as though I was fed so much rubbish at your age - Go to Uni, much better job prospects, high salaries, head hunting of graduates... etc etc - rubbish.
If you're anything but stunningly gifted you'll go through the standard "sausage factory" and hopefully have a degree at the end of it, along with a pile of debt. It's then really up to you how you use it.
I live oop North, so a 20k salary for me isnt too bad at all. 20k or even 25k in London, id probably go hungry some nights!