The WA statute of limitations is 6 years on written contracts and 3 years on oral contracts.
So you still have time to sue.
Anybody can sue anybody for anything so, yes, she can sue you for harassment. She would just not be able to make it stick. She's blowing smoke hoping to scare you away.
Joane:What is the Washington State statute on first
party debt collection?
There is no such thing.
She owes you, she won't pay, you sue her. Period.