Welcome to HCM.
It is quite natural that if one does not eat properly, that person is bound to feel tired and lack energy to do any thing.
What is needed is to find out the cause of her not eating well. You have not mentioned the age of your wife. Loss of appetite has different causes in different age groups.
You should consult a physician, get a thorough examination done along with various investigations including ultrasound
scan to detect the cause of her loss of appetite. If the cause is identified treatment can be started to rectify that cause. If no cause is found. anorexia nervosa
has to be considered and you will need an appointment with a psychiatrist
for your wife.
Wishing your wife all the best.