My husband has three sisters with kids. They are always doing things together with their kids and leave us and our little ones out of it... whether it's just hanging out, taking trips, or going on full blown vacations together. They never invite us nor let us know about anything they're doing. I am always learning about it from Facebook with their regular posts & photos taken together. Not one of his sisters will even text to ask how we are, how the kids are. I feel like we barely exist to them and it doesn't make sense.
What really gets me going is that they and all of their kids are so close, but never see, ask about, or involve our kids in any of the fun. I would love for our kids to have some kind of relationship with their cousins who are all good friends. It's really confusing & hurtful to me while my husband is really ticked off about it and has given up on caring anymore. I'd shoot them a friendly text or ask if we could get together sometime but I feel so unwelcome to. They never have an interest
Re: In-laws and never being included
Do you guys have different lifestyles? Do they SAH while you work? Or vice versa? Maybe they think you are busy.
I have friends that rarely include us in plans that aren't kids bday parties. They are home during the day, while I work. Yes, sometimes it makes me sad to see them all having fun, but I'm not reaching out to them on the weekends either. Does this rambling make sense?
OP- If you don't put yourself out there, you will never be included. Invite them places. Host a cousins playgroup. Offer to have the cousins over for a sleepover or just pizza and pajama party so the parents can go out for a kidless dinner. Be vocal on FB "Aw, it looks like you guys had so much fun! Dd loves the zoo. Call us next time and we'll tag along!" They probably have no idea they're upsetting you.
On the other side, be prepared to see your Sils all the time when you start getting invites. You may just want to keep quiet!
Your DH could invite them over for a bbq and present it as a chance to have the children play together. Make a ton of water balloons and mixed drinks. It's easy to start with something casual centered around the children.
I also agree with inviting them to do stuff.