S, I never give up on anyone. What I usually do is step back, wait and when the student is ready to listen to what I have to say, I will then return to provide more input.
What your h told you after his sister passed away is how he perceives things for now. I seriously doubt that he came back just because of "guilt". Listen, do not pass judgment and come to understand that there are going to be times that his "speak" will be of of misconceptions and you will need to sift through his "speak" to get the answers.
Now is the time to take care of YOU! Try not to allow what he says to get you down. Just remember...you had many wonderful years together and they were not from your imagination. Focus on today and allow tomorrow to take care of itself.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.