Just to clarify @Glisten - this is an involuntary change in behaviour that comes about, and are you saying it usually precedes big changes? Like your body knows some change is coming? 

Sounds like maybe a bit of a trauma response, potentially? But it doesn't sound unhealthy to me - even if from the outside it looks like you're self-isolating, seems that your internal experience is more that you're ensuring you have reserved enough energy to be able to take on the coming tumult. 

I agree, change is not bad, in fact it is inevitable! What's the saying, 'In life, the only constant is change' right? If this helps you to mitigate the impacts of sudden change, sounds very helpful indeed. Is it something you feel concerned about or scared of?