I'm so sorry for the loss of sweet Miles. May he forever hop in your heart.

As for grieving Ella, bless her heart, spend LOTS of extra time with her (this, of course, calls for extra parsley ). That's the best advice I can give you. This is one of the reasons I prefer "single" buns to bonded pairs--it breaks my heart to see them grieve.

NOT to scare you but....
I would take Ella to the vet ASAP incase Miles had something contagious. I WOULD NOT purchase a new bunny friend until Ella has had a check-up.

You might PM Daisylover for advice... she's a bunny behaviorist.