Marriage is a process of trial and error like in any partnership. Perhaps the fact that you had actually gotten married had put a strain on both of you on some level. (as you are saying he is not paying much and that can be very stressful in a marriage)
The fact that he walks off when you are having a disagreement is common to many men. This is a self defense mechanism. They do not like to feel blamed and always want to feel in control.
Hopefully many of his behaviors or personality traits are not new to you having been involved for 5+ years.
If possible, see if chores around the house can be delegated. That way you won't feel burned out. If he does not help nothing is stopping you from not doing his laundry. Even Judge Judy had done this number on her husband and he then had to do something after a week without clean clothes. After all, deep down inside men want to be taken care of whether realistic or not of an expectation.
Try to talk to him when there is no argument at hand. Perhaps make some time after dinner and also try to suggest marriage counseling. This would be quite helpful since you have so many things on your mind. Of course, he ought to be willing to give it a try. A marriage runs due to the effort of both parties.