I'm fed up with a grieving friend
Why are you fed up with a grieving friend?
I don't feel like grieving with them.
You need to be more available to your friends when they need you. You are not behaving in an understanding way. Your friend will not be available to you when you need them to be if you are not more understanding.
That's not true. Let me be a bit selfish, I deserve it since I'm so caring.
It can be really hard to lose someone you are close to. Maybe you don't feel the same way but you can be there to listen or hangout for a little bit. Your friend will really appreciate the fact that you even care.