You need the assistance of a good attorney.
Because your loan wasn't in writing, you may not be able to sue for performance for a couple of reasons. Most importantly, the statute of limitations on oral agreements is usually three years. You're beyond that by a year. The payment stream, however, may afford you some additional options since it would appear to ratify the loan, and extend performance to a more recent date.
You need to act quickly if you have any hope of recovery. Good luck.