Earthmama... I am so sorry for your loss.

I agree with Echoes - is it not possible to tell them that your friend died? You do NOT have to share anything with them that you don't want to, but you would no longer have to hide your distress from them. If they ask questions, it is entirely okay to say something like "I don't feel up to talking about it, but it means a lot to me that you understand why I feel so emotional today."

No need to compartmentalize. You can be true to you, and real with them, even without disclosing details.

Hope you find the best way to get you through this sad time, EM.