Dissociation really happens on a spectrum. Almost everyone has had a form of dissociation at one point or another. Driving home after a long day, and realizing you don't remember the drive, is a form of it. Being bored and staring off into space, caught up in whatever is in your head, can be it also.

But like any other spectrum, there are levels of severity, and often levels of distress that come with it.

For example, the two I listed are kind of normal, but if they were to really bother a person, it may be worth asking or talking about. Also, there may be someone who loses chunks of time, but it doesn't really bother them. It is still worth asking about, because that is more severe dissociation.

A couple of the things you listed, holidays and dealing with loss... both of those can cause "normal" dissociation. Both can make us all want to hide, or at least me because of anxiety and avoidance, and dissociation is a way to disconnect and separate from what is going on externally and sometimes internally.

But if it bothers you or if it lasts a while and doesn't get better, it is definitely worth asking about. Trust me, your pdoc or t would rather you ask and it be normal, than for you to keep it to yourself and it be a real problem.