They say a liver commonly repairs itself from an acute damage that lasts for a very short time. so my question is, how can a decade old alcoholic person progress to liver cirrhosis? why does the liver stop repairing in that case?

A decade is a lot and no longer acute, but rather chronic damage, and once the liver’s ability to heal is overwhelmed, normal hepatic tissue is replaced with a fibrotic scar. Individuals are different in their ability to heal and recover with some extremely sensitive to such damage.

Agree with Dr. P. Chronic alcoholism is not the same as acute hepatitis A from which liver can recover. Chronic alcohol use caused fibrosis and that is not reversible. Abstain from alcohol. There is no safe level.