Uncle John is a lonely older brother of Pa Joad. Uncle John had a lot of bad situations in life, but the last one changed him a lot. During a long period, he felt responsible for the death of his young wife while the last was pregnant for the first time. Now let’s get it, why he felt responsible for that? Well, in a middle period of the pregnancy she felt not very good and said John to call a doctor as her stomach hurt so much. He refused, saying that she had just eaten too much food. He was sure there was nothing special.
Next morning she was leading herself like a crazy woman, she was totally out of her head, and soon she died from a burst appendix. Feeling so sorry after that situation he found no better way than drinking alcohol to forget that entire situation. He thought it was a sin and he has no chance to atone for it. He lives with the burden of this individual sin, which seems to become overwhelming during times of family crisis. His only desire was to drink that much, not to be able to remember, and feel anything.
Also, when he was not drunk, he was always doing different haphazard charity. He felt so much guilt for that negligence he did to his wife. We wish that someone would give him a lesson of the importance to let things go and understand that what was made cannot be unmade. But it is pretty clear that the ship of John's health and happiness has sailed with the death of his wife and child.
Uncle John Joad in the Essays