I'm going to break up with a girl because she in the past had severe depression
Is this really the reason for this action?
As expected, it's the cause of that break up.
If you feel your girlfriend is depressed then you should try and help her out. This is what a partner is suppose to do, support their significant other. If you feel it is something that you can not handle however, then breaking up may be the best option for you.
I'm going to hurt her so bad. I took some of her favorite things. I'm going to make her go insane.
Why would you want to kick your girlfriend while she is down. It would really help her out to be supportive of her during this time instead of being hurtful.