If you really want to win my heart, demanding that I buy you things to "prove my love" is not the best way to do it.
Seriously, dude? You should be buying me stuff. You should be bring me presents and giving me flowers and making me feel special, and treating me like a princess, not like I'm your personal vending machine. Because I'm not going to give you anything.
If you really want to win my heart, you might try talking to me-- even when you don't want anything. Better yet, listen to me. Yeah, try listening every once in a while.
It won't work, but you might try...
Now go away.