Were you able to have any honest discussions with him prior to his leaving? How was your relationship during the years before you married? You do have a lot invested in your marriage.
It could be an important start toward sorting out your feelings if you could ask him the questions that you have posted in the forum. Let him know that you want to work to repair your marriage. It must be a joint effort though. You should not be expected to give more than he does.
Best of luck to you–
🙂