Honestly, you're probably already doing what you should, but there's really only so much you can do. You can tell him soemtimes you wonder about what's best and ask him what he'd prefer. It helps me when my friends are geberally comfortable when I'm struggling. That they don't internalize my anxiety or struggle. That they are able to be present in it without trying to take some of it on or be concerned for me. They know it sucks, they know I deal with this all the time, so they just exercise extra patience when it's extra bad. Sometimes I'll motion for help, but otherwise they just wait. We've had many "what should I do" threads before so maybe you can find them for multiple answers.