As
@MAWBD2 said he needs to actually leave his house. More so what he needs is to go on like a one month break and spend a bunch of time outdoors and around regular fucking people who aren't dents, detractors or downies so he can get some perspective about shit. But I get the feeling he is too far gone for that to happen - he wouldn't even take the invitation from triple P to go on a paid vacation (which I have to say was one of the nicest gestures anyone offered DSP in a long, long time)
I've done a bit of travel but have also had periods where I have been isolated and it really wrecks your mental health rapidly.