Do you really need all that stuff on your "to buy" list? Start another list of all the things you're thankful you already have in your life.
Write down whatever pops into your head. Great friends? Pretty hands? The world's best parents? A loving pet? Just the act of writing them down will switch your mindset from thinking about what you don't have to appreciating what you do.
The lists will balance each other out. In fact, you'll probably find the appreciation list is longer! Who knows? You might decide to be a little more thankful and make do with a little less.