Your blended family isn’t blending and your husband is acting like it is new information that maybe, as one of the adults in the mix, he has to take a lead in moving things along. I’m guessing that some important conversations didn’t happen when you two were deciding to tie the knot. Either that, or the reality of it all didn’t penetrate. There’s some important and difficult work ahead for you all. Done well, everyone will benefit from a new sense of family.
Your collective kids are going to be “home” for awhile yet. The issues can’t be avoided without there being a blowup or blowout at some point. If you two want this relationship to last, it’s long past time to talk about (and commit to) befriending the older kids and parenting the younger ones – together.
“Home” doesn’t happen by magic. “Home” is a function of the heart. It takes time and energy and, yes, love.
I strongly suggest that you two get into couples therapy. If you could have sorted this out on your own, you would have done so already. You need help dealing with the realities of your new family. You need a safe place to talk out expectations, disappointments, and what you are going to do now.
I wish you well.