Do you have a therapist to run this by first? When I was having a tough time in my MBA program due to severe depression, I communicated this to my professors (one time in tears to my great embarrassment). They all fortunately understood and worked with me and I graduated with a 4.0. I'm conflicted about whether you should tell him because he seems self-absorbed (talking about his hobbies). In my situation, I did. Him having additional information to work with (including your request for acknowledgement) could be beneficial to you. What harm could it potentially do? Just my thoughts. I hope you come to a decision that brings you peace.