The thing with the In-Laws is tough - its oneof the issues that pops up all over the boards. I always feel a little sorry for the In-Laws. Ultimately, your H is still their family member and they love him and want to be in his life.
Oddly, in my sitch, my MIL adamantly declares that she wants nothing to do with OW, and I'm the one that thinks that is not a realistic stance (if the relationship endures).
Here's what you can do- proactively work on maintaining good relationships with your MIL, SIL and other family members. You will always be the mother of the grandchildren and you will always be in their lives in that regard. The best course (I think) is that your In-Laws shouldn't feel like they have to choose bewtween you, but that they can have a relationship with both of you. Even though its been a year, its still pretty early on, and the family members that feel like they have "shut you out" may still come around somewhat. Leave the door open for them.
As for them being a happy family together - you know its highly unlikely for that to last, right? Even if they beat the odds and somehow end up in a functional marriage - they will still have the ups and downs of real life.
