It really took me the longest time to realise that a huge percentage of people that need to go outside as much as possible do so because they feel unhappy at home (‘home’ as literal dwelling I mean, they don’t know what to do there, aren’t happy with or can’t be by themselves, don’t enjoy their immediate home environment & stuff they have in it, etc).

Humans are social creatures. Many animals get depressed too when they don’t have another of its kind to live around.