I'm annoyed that my gf warned me she will be sad on the anniversary of her brother's death.
Why would this annoy you? As her boyfriend you should be concerned for her.
I don't want to deal with her being sad.
You shouldn't be upset with her for grieving about the death of her brother. Try to support her through this sad day.
Nah, I think that she needs to deal with her emotions and stop bothering everyone with them.
That's really selfish of you. If you can't support your girlfriend then you should not be her boyfriend. She deserves to have someone that cares about her feelings.