What can I do if my wife suffered an extreme case of shingles two years ago. Can she receive the shingles vaccination?

Probably yes. A person can have shingles more than once. Her primary care doctor can evaluate to see if there is a weakness in her immune system (or just bad luck, older age, or other bodily stressors) that allowed her to have the first case of shingles. The doctor can give some advice on whether or not the patient should get the shingles vaccine to help prevent a recurrence of shingles (some age limits apply).