It sounds like the lie must have been a big deal to this friend of yours. The seriousness of the matter may have been compounded by the length in which you held out maintaining the lie. I wouldn't know I'm just surmising. If you confessed, apologized and tried to make it up to your friend then perhaps they need time apart from you to think. Let your friend know that you care. Maybe send a card or letter of apology. Ask if your friend will consider being friends again down the road.

I've had a friend apologize to me for something but there were many incidents before and they all added up making it difficult to forgive the last incident. I don't know that we will ever be the same. It is sad to lose a close friend. I hope your situation finds a better ending than mine.