I'm 20m and I have a slightly different take on this one, I'll probably get downvoted.

Perceived spaced does not put you under any obligation to interact with anyone.

So if something is up and you want your space, you can get up and leave but its not possible 100% of the time.

I zone out a lot, I lost my mom, I was raped, have a messed up relationship with my.dad's side of the fam , I'm 100 percent no contact and I have depression. My whole being is dedicated to protecting my space, whether I'm in public or private. Slightest thing can trigger me.

There's therapy and meds but sometimes that void is accelerated and you have no option but to tune out from everyone.

I'd say give her time and then ask what's up, or wait till she opens up to you