He is one of two things, afraid of people he may meet or uncomfortable around people. So he is doing this so that he can avoid going to these places. I say this because I used to have the same thoughts. It is a process that needs to be worked through.
Good luck, it is more his problem than yours.
Please be careful to not give in to him and leave him home because this will allow both of you to create separate lives and that will lead to the death of your marriage.

Good luck.

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