Oh, I'm sorry that happened. How old are the birds? If they are very well-trained in roaming and returning she might come back.
She could roam, esp. if she's now foraging for food.
Good luck. I lost a...
I keep my girls in a coop b/c it's more secure. If you think it's secure, really secure, then I can't see why it's a problem.
Are your winters harsh?
Personally, I'd keep at it b/c I like to have some...
Can I add a Q? Is it possible to breed w/ a rented roo? Do people stud a rooster for those of us who don't want one in the flock? (Sorry for piggybacking BlueGlassJar!)
Your EE is likely a mutt so no telling when it will start. It's not a hard and fast rule and not all breeds/individuals are the same.
Chickens teach us patience?? Yeah, doesn't work for me either.
Good luck....