Does this happen to you?

I have depersonalization because of anxiety/PTSD and I've noticed that often when hanging out with people I will "space" out and remove myself from the situation and feel suddenly like I need to go home.
It especially happens at frat parties and crowded places (tldr I'm a college student ex sorority girl)

It really bothers me because of how youthful/extroverted I used to be, loving concerts.

I've been experiencing the same since I was little.

I get that too... That's why I don't really hang out with anyone because whenever I'm at a party or something, I'd suddenly get a strange feeling and I would think to myself, "What am I doing here?" and zone out for a long time. Everyone gets mad at me for not wanting to hang out with them, and I try to describe my problems to them but they don't understand :/

Same here. If in a crowded place I am ok as long as we are not too close to one another, and it's not super loud and hectic. A concert i'm ok with because the loud music I like.

This has been happening to me lately. It's just started to happen to me, so it's extremely frightening for me. It's hard to explain to other people, so I don't tell them what's happening.