I'm going to burn the gift
Why do you want to burn the gift?
Because my girlfriend bought it for me!
It is okay not to like a gift but you shouldn't destroy it. You could always return it.
No I'm going to burn it, I don't care about what my gf will think.
She'll get hurt and probably will break up with you for having such attitude. As I said, If you don't like the gift you can return it or give it to someone else.