My (25F) husband (26M) kicked me out of a group outing but I’m struggling to understand why

My husband and I had made plans with a group of friends (4 other people, including his ex) to go out for dinner at an Asian restaurant. We created a WhatsApp group that just went silent.

Yesterday, my husband told me he would be meeting with one of the guys in the group for dinner after work, as their workplace is near each other.

I found out that he had lied and was actually going with the whole group for that outing that we had all planned together (I had even picked the restaurant) behind my back.

So he basically kicked me out of the group and wouldn't tell me why. He just says he doesn't know why he did that.

I'm really confused.

I'm thinking he must be embarrassed of me. That maybe he thinks he's downgraded when he married me?

What could be the reason?