Layla sounds just like Hallie when I got her (it was a different situation but the situation I was in sounds the same). She needed to be socialized and while it's been a LOOOOOOONNNNGGGGGG process she is getting better and I can see improvement. Keep in mind it's been 2 years and I'm sorry that's probably not comforting
I think you are doing the right thing, you can't keep her isolated forever, just like I couldn't keep Hallie away from other dogs forever nor do I want to. Keep your head up, you are doing the right thing and I know it's hard for you. Good Luck and tell Layla that those little puppies aren't the enemy (hehe).