First of all, don't worry - you will not be out on the streets. Secondly, read through this website - you will find lots of advice.(posted 8443 days ago)I would recommend that you write a letter to the lender asking a copy of the "completion statement" from the sale of the property and supporting documentation, then just sit back and wait.
You say that you were first contacted in 2000, this could well be on the 6 year limitation period limit depending onthe exact date. This could be a good argument for you, although you will see from the website that the 6 year / 12 year limitation periods are a grey area.
Write that letter, and please try not to worry. Come back to the board when you've got your reply and we'll take it from there.