Hi - we are in the same situation - DH has 4 kids all with kids of their own. Oldest DD does not talk to him, no one can figure out why. Next oldest lives in Europe, she does make an effort to come see us when she is over here. DS & wife live about 3 hours away, we go to see them when we can, but they never come to see us nor do they invite us down there. We always have to be the ones to invite ourselves (I HATE doing that). DS2 lives about 4 hours away and is planning to move 2K miles away for his job.
Ladies, please, if you are a DIL, PLEASE make an effort to include your DH's family in your plans. So many guys leave the social aspect to their wives and just go along with what they suggest, so they wind up socializing more with wife's family.