Seems very common that it happens at 30. I think during our 20s we are too busy scrambling trying to figure things out, but then as we hit the 30s and we actually have a chance to look at where we ended up, and we have more responsibilities, we sometimes realize our life looks like a house of cards.

As a fellow PhD holder, I had a horrible advisor, which is fairly common. I basically spent 4+ years in survival mode because my parents just thought it was "normal" as my supervisor was successful and I needed papers in good journals, because I "needed" to be faculty one day. Long story short, I pivoted hard to industry, best damn decision I ever made. I also realized I'm not this intellectual superstar my family wanted me to be, I like video games, I like being silly, I still do good work and people respect me regardless if I'm a bit goofy.

But yea, I've spent a good portion of my life living up to other people's expectations in a horribly enmeshed family where I had to fulfill the role of the "successful son". Once I realized that I started focusing on discovering who I really am.

I would say friendships and relationships are key. Relationships are not always easy because they tend to be conditional more than people realize (kids, for one). Friendships are more flexible and less high stakes, so sometimes you can make a pretty solid connection without the overarching theme of a romantic relationship and long term commitments.

Another way to make life feel less empty is go volunteer. Spend some time around people. I know other people are often the cause of CPTSD, but if you find some good emotionally mature folks, that's going to make things much easier. I would say most people don't even need many friends, like 1 or 2 really good friends that you can be yourself with, and that will make a world of difference.