Peaked in high school

Sign of people who peaked in high school: they keep talking about high school.

Now it's great to be reminded of the past from time to time, but you can recognize these people by the frequency of how much they keep referencing the past:

1. the relationship they had
2. how cool they were
3. who they knew
4. what they did...

and there are some people whose entire current group of friends is the one from high school they hung out with. And their identity is entirely based on whoever they were in high school.

As if the last time they ever felt happy, was back in high school.

My suggestion is to stay far away from these people.
They don't grow, and haven't for quite some time.