Given how kind you are and how you felt about him, you likely provided him with a measure of comfort whenever you worked with him. I totally believe this because you have provided me with comfort and encouragement when my life was at its darkest. You are such an amazing person. Try to remember that we all go through times in our lives where we face things alone. I bet this gentleman wouldn't want you to worry about him. He is in a better place and my POV is that he may be blessing you from where he is at now.

Most of us, do not want to leave the people we have liked or loved in distress. It is so important to take care of ourselves first so that we can continue to shine our lights to others. That you feel so deeply for others has blessed so many of us. After you grieve this, remember that you were a blessing to him. Hugs to you dear friend.