Ted is damaged goods. He had a miserable childhood. Both his parents had severe problems with alcohol. They had marital problems and his dad abandoned the family. His sister died after severe problems with alcoholism and drug abuse. Ted has had his own well documented struggles with alcohol and an inability to keep friends.
Many people who come out of situations like this are overachievers but unfortunately their difficulties still end up taking their toll. It often manifests itself in bad decision making such as extramarital affairs and heavy drinking. Ted described himself recently as a “Scotch man” in an Anderson Cooper “town hall” despite coming from a family with a propensity toward alcoholism. Ted looks ten years older than Marco Rubio even though he is approximately the same age. Sadly, Ted is a tortured soul.
Your analysis is sound, imho. People with wretched family backgrounds have a hard time not carrying the scars and being crippled by them. It took me some decades. I think Cruz is a product of his and has not taken the steps to be his own man.