Friendship advice

Hi everyone

So I have a friend, who's partner about to have a kindey transplant and my friend is giving one up. 

I'm fearing, that my friend, is going to shut down on me talk wise, I'm afaird if that happens, I will worry and wrong think.

What do I do. I'm just not sure weather to talk on it with her or let her come to me to tell me. ?? 

Thank u 

Lizzy