What happens to someone who has bulimia for decades?

It varies: If one is adequately treated, then he/she learns to cope with the behavior by avoiding situations that are stressful and may cause him/her to binge.In addition to treating coexisting conditions like depression etc, making changes like eating small but frequent meals, eating with others, hobbies & avoiding being alone after meals improve the outcome. If untreated, the problem continues.

Chronic illnesses: Most physical problems associated with bulimia arise from vomiting. Teeth will eventually decay and fall out. Blood potassium levels decrease, a risk for cardiac arrhythmias. Stomach ulcers may develop as well as esophageal bleeding and tears. Over time, a sequence of chronic illnesses can occur affecting heart, liver, gastrointestinal tract, and/or neurologic complications.