8. They Will Help You Justify Any Decision
If you want to buy a birthday cake to eat but it's not your birthday, your friend will help you reason out why this isn't a crazy idea. If you really want those shoes even though your bank account is begging you to reconsider, your friend will help nudge you to the cashiers. If you really want to put on that sexy little number but are worried what people will say, your friend will already be standing in your closet, pulling it off its hanger. 

Sometimes you need to listen to that devil on your shoulder, and your best pal is that.