He is showing you the pattern he follows where he binges and he is forty years old now, still living this same old pattern. This is exactly what I myself failed to see. Be good for a while, then begin being toxic again. Actually, a therapist explained exactly what I have been dealing with to me. This is something this ex has to work on, not anything YOU can fix or change. This ex needs to stop drinking and partying and learn to stop binging and it can take the rest of his life for him to correct or gradually change his behavior pattern. Some people never really change this pattern because they simply never learned how to work through their challenges. Instead they just learned to escape through their binge drinking/drugging.