Valve Surgery

Hi, My mother( 65 yrs) had surgery for valve repair almost 12 years ago now she has symptom for valve leakage Doctor is recommending for surgery to replace valves but she is totally against it. Since childhood she has depression problem & she is diabetic.Is there any treatment without surgery? At any cost she don't want to go for surgery. Its already 6 month she has symptoms for valve leakage and she is not willing to co-operate with surgery may be with the time she will realize that surgery is the only options. How long it is ok to wait?

Thanks & regard

Sunil