Don't worry Kirsten, your little Lily will adjust just fine, but I can't believe that your friends have gone against your wishes to keep her inside. I would definitely get her sooner than you planned.
Also, so what if people critizise you for the way you treat your cats. If they want to let their cats outside and sit in open windows with no screens, good for them.
Go with what you feel in your heart. Personally, I feel you are a very good meowmie.
So when others say this or that to you, just let it go in one ear and out the other.
You're doing a great job. At least your babies will have a long and happy life.