I lost my own 8 years ago. It's easy enough to withdraw but social isolation isn't a good solution.

Thinking about codep tendencies and reading your replies, and it's something that I've certainly done before and have tendencies to do, it's minimizing feelings by justifying behaviors that are not a good mesh. It's rescuing others from consequence. Not consequence in a punishing way but cause/effect type of way where there's a need to recognize that the other person-you- has feelings that need to be considered. It's self neglect which is probably learned from childhood.
It sounds like by him telling you that he doesn't open up because all it does is cause an argument feeds into your retreat to not cause harm/upset feelings.