Husbandsfamily (advice please)

Ye

So my husbands family has had these get togethers where only they can attend. No wife or kids just them. According to him it’s to spend time together just them because they don’t do it often which is sorta true. But to me it’s wrong I don’t like it at all. I feel like we the spouse and kids should be invited as well we are family too. My family never has events where only we can attend, my family is very open and very welcoming in my point of view. I’ve tried talking to him about it but when it comes to his family he becomes very defensive as do I. I just don’t know how to deal with it cause it honestly bothers the hell out of me. He says its because I always want to be included in everything but I mean isn’t that marriage? Aren’t we suppose to be one and tell each other everything? My Parents hace that Kind of relationship and it’s what I’m used to. His parents are getting divorced and barely speak a word to each other.