There are 60 vials in the pack of Restasis I received. Do I use each vial 2 times or one time?

I "was told" that you can use one vial for both the morning and night drops as long as you refrigerate it, since it doesn't have preservatives. Now, I am telling you, my insurance won't cover restasis, and it's very expensive. I leave my vial in the fridge until it is empty--I get a good 4 days out of each vial. One box of restasis can last me 3 months, and it works fine--as long as it's refrigerated (I cover the tip with saran wrap to make sure it doesn't get any germs in it). I've been on restasis since July, and have seen a dramatic improvement--I think (no, I know) that the company wants you to have to buy 60 vials a month, since it's so expensive. It's not necessary.