It is more effective to calmly disagree and discuss a subject than to display anger. When a friend has a struggle with something that matters a great deal to him but he hasn't overcome, behaving non-judgmentaly will create more appreciation in our friend than we might imagine. That's something we really need to think about. Encouraging a person to overcome a weakness is fine. Insisting by our attitude that a friend must overcome a weakness, or turn it into a lifelong obsession, puts a lot of stress on a friendship.
Friendships thrive on it.
If you would build a friendship, be nice. A card, a gift, a letter, praise, and appreciation keep the friendship account full. If she thinks an anniversary is the most important time of the year to her. We had better play up that day as much as we can. Get her flowers, take her out to dinner and attempt to satisfy her every whim.