sabau2, The medical name for what may be going on with your ex is calls "wet brain" or Wernicke-Korsakoff syndrome. This is from an online medical encyclopedia:

Wernicke-Korsakoff syndrome

Definition:
Wernicke-Korsakoff syndrome is a brain disorder involving loss of specific brain functions caused by a thiamine deficiency.

Alternative Names:
Korsakoff psychosis; Alcoholic encephalopathy; Encephalopathy - alcoholic; Wernicke's disease

Causes, incidence, and risk factors:
The syndrome is actually a spectrum, including two separate sets of symptoms, one of which tends to start when the other subsides. Wernicke's encephalopathy involves damage to multiple nerves in both the central nervous system (brain and spinal cord) and the peripheral nervous system (the rest of the body).
It may also include symptoms caused by alcohol withdrawal. The cause is generally attributed to malnutrition, especially lack of vitamin B1 (thiamine), which commonly accompanies habitual alcohol use or alcoholism.

Heavy alcohol use interferes with the metabolism of thiamine, so even in the unusual cases where alcoholics are eating a balanced diet while drinking heavily, the metabolic problem persists because most of the thiamine is not absorbed.

Korsakoff syndrome, or Korsakoff psychosis, tends to develop as Wernicke's symptoms diminish. It involves impairment of memory out of proportion to problems with other cognitive functions.

Patients often attempt to hide their poor memory by confabulating. The patient will create detailed, believable stories about experiences or situations to cover gaps in memory. This is not usually a deliberate attempt to deceive because the patient often believes what he is saying to be true. It can occur whether or not the thiamine deficiency was related to alcoholism and with other types of brain damage.

Korsakoff psychosis involves damage to areas of the brain involved with memory.

Expectations (prognosis):

Without treatment, Wernicke-Korsakoff syndrome progresses steadily to death. With treatment, symptoms (such as uncoordinated movement and vision difficulties) may be controlled, and progression of the disorder may be slowed or stopped.

Some symptoms -- particularly the loss of memory and cognitive skills -- may be permanent. There may be a need for custodial care if the loss of cognitive skills is severe.

Other disorders related to the abuse of alcohol may also be present.

Complications:

Permanent loss of memory
Permanent loss of cognitive skills
Injury caused by falls
Difficulty with personal or social interaction
Alcohol withdrawal state
Permanent alcoholic neuropathy
Shortened life span

I don't know that this is the case with your ex, but alcoholism is one tough disease, on many, many levels.
Richard