How to deal with family who don't care

I don't know how to start this because I don't want to leave out details, but I also don't want to add every detail and make it long.

So bare with me.

My husband's family is nothing like mine. My family is very close, very tight, very important. His family his somewhat close, but not at all. His main family such as parents and siblings use to live an hour away from us. They came to see us within two years literally 6 times. Where as we would always go every Sunday since his mom would do Sunday dinner. There were times we couldn't always make it cause of my husbands work schedule but we always made it up on another day. We would call and ask a couple times to go to the zoo, or to some event that was going on around them. Which they did go to. But his mom always brought her granddaughter with. Which I guess was a given since she was kinda raising her on the weekends. Well our time with them has kind of dwindled when my husband got a new job in a new state that was an hour away from our home. His work schedule became even more chaotic and we barely ever made it to his parents house. But yet again, his parents never made the effort to come see us. At all.

So with my husband's new job, we decided to move to that state he was now working in because I hated him driving late at night just to get home. Or having to wake up super early. His family never once came to see us, we recently found out we were expecting our second baby, and they didn't even come to the Easter/gender reveal party. Not a single person from his family showed up. His parents then decided to move to North Carolina which is far from us. They never came to see us before they left. Or even offered to meet us half way to get together. His mom excuse was that she doesn't like to drive so far. Which at this point would be a two hour drive for them.

So they have moved, and today my husbands dad (technically step dad) shares a picture of a shirt that says 5 things you need to know about my grandpa. And tags my husbands sister only, the one with the niece. Didn't tag my husband or I. So it set my husband off. His mom said she didn't like to drive, yet she drove all the way to North Carolina, which is about a 27 hour drive if not more. They never call or text to ask how our son is doing. Yet his mom will be the first to comment on a picture I post of him acting like she loves him so much. They drop anything and everything for their granddaughter but not once for us or our son.

It just breaks my heart so much. It hurts me for our kids because they'll never really know them. And they are missing out on so much greatness because our kid is awesome. But it really hurts me for my husband. He's always been the black sheep of his family because he's the only one who is successful, who doesn't need his mommy all the time, who doesn't have a criminal record, who went to college and graduated. So he says he's use to it. But damn it just hurts. My family loves him more than they probably love me lol. My family adores him, and I wish his own parents could see how amazing he is too.

Part of me feels guilty, maybe it's my fault? Maybe I could have made more effort when he was working? Another part of me feels like it's not though. I'm not going to force someone to be in my life or my son's life. I just don't know how to deal with this stuff. Do I say something? Do I let it go?

I forgot to mention that when his parents did move, they didn't even tell us when they actually were. We found out through Facebook when they were already on the road.