The benefit to going out, enjoying your life and being around other people IS that you are doing those things. You're hopefully then being happier, you're not worrying about your skin as much, you're doing the things you want to do regardless of acne. And maybe having a positive outlook and trying to enjoy life means you're not stressing so much and that's helping your skin - because we know stress and acne are linked (at least for some people).

Don't know what you're friend is going on about with the bacteria etc unless they're referring to how immunity is normally built up (immune response to recognised antigens etc) but that wouldn't have anything to do with acne - that's more for illnesses

The benefit to going out, enjoying your life and being around other people IS that you are doing those things. You're hopefully then being happier, you're not worrying about your skin as much, you're doing the things you want to do regardless of acne. And maybe having a positive outlook and trying to enjoy life means you're not stressing so much and that's helping your skin - because we know stress and acne are linked (at least for some people).

Don't know what you're friend is going on about with the bacteria etc unless they're referring to how immunity is normally built up (immune response to recognised antigens etc) but that wouldn't have anything to do with acne - that's more for illnesses

Isn't acne an illness though? Can't acne be a result of a immune response from the body?

By illness and immune response I was meaning things like viral infections etc where being exposed to the virus (by vaccination or having the illness) your immune system 'learns' the antigens of this virus so if exposed again you're not as affected by it or not at all effected by it. Sorry this explanation isn't great - it's been a while since I was looking at immune response.

But I suppose in theory acne could be related to immune response due to inflammation maybe? But I don't really know

Of course it does. For other reasons besides the bacteria. You keep talking about stress and poor sleep. Are you hiding away indoors because you have a little back acne?

I don't think it has anything to do with bacteria. Most of us are forced to go out sometimes. I was forced to go out for work even amidst the worst part of my eating disorder/anxiety/social phobia and body dysmorphia. I was cleaning people's homes so I'm sure I was exposed to tons of bacteria. My skin didn't get better until I was properly medicated.