Am I wrong about this ??

Can someone tell me if I’m wrong in this??

I don’t know if it’s because he is nervous, but every single time my bf is around my family, he blurts out things I don’t want my family to know.

So today for Thanksgiving dinner, someone was talking about cars and driving records and my boyfriend starts talking about how he totaled a bunch of cars in the past when he was in his teens and early 20s. (He had a drinking problem). But he is sober now and a completely different person.

Anyway, I didn’t know him at that time. But he has told me all the mistakes he’s made. And I accept him for who he is.

However, we haven’t told my family all of his past. And that’s because

1. They never asked.

2. It’s none of their business really.

But when he told everyone he wrecked a lot of cars in the past, they made some jokes and laughed, but I saw the look on my mom’s face and it a bit judgy.

When we came home, I told him that I wished he didn’t tell them that. And he said he should be able to be himself with my family , which is true, but you can be yourself without saying certain things.

When I’m around his family, I don’t tell them every bad thing or mistake I’ve ever made in my life.