Good luck sweetheart. Please try NOT to panic, stay calm....... In the first place, unless there is written communication, it will be very hard for her to prove anything. And if the puppy was sick, get documentation from your vet to help build a case. Maybe taking the approach that -- "yes I said those things and they are true" might work.
Law suits are very scary, sending hugs
and I will carry you close to my heart. When is your day in court?