No offence was intended your way.
However Grant, although he had a low tolerance for alcohol, did drink to excess, and even more so whenever he and his wife were separated for whatever reason. Maybe Julia was his stay.
I disagree, respectfully, that he drank often. He just drank poorly.
Your 100% correct. Julia was his life. He drank most and worst when he was away from her for long periods without communication.
It's a pleasure to discuss this topic rationally and without emotion.