I feel so sad for all these families losing out on seeing their grandchildren,unless you have done something horrible ,you should be able to see your grown up kids and their kids,I don't believe you should just shut out your family because you have a partner and a family,they still bought you up and cared and loved you,and made you into a person someone else loves too!
I see some of you ladies have put ,that your kids in owe you nothing,I disagree,I think you are still owed love and respect,children get some much from their grandparents,it's very enriching for them ,to spend time with their extended family.
I have grown up grandchildren aged 16 and 17 ,and do not see them for a few weeks,but I message them on Facebook,and sometimes they say to my daughter ,their mum,I want to see nan and grandad and they will come over ,and join us on days out.
They count themselves very lucky to have two sets of grandparents,so it's a win,win for everyone!
If it was me ,I would want to know what is wrong,I don't think I would pussyfoot around,I would directly ask my son ,if there is a problem ,you have helped them a lot,as of course a mum and nan would,but I would feel very shut out in these circumstances.
In other cultures the family is more of a unit and kids, aunties,uncles, cousins and grandparents all see each other and all these relationships bring so much to children.
I taught primary and Secondary school for years,and grandparents are so valued by any age child.
Try to find out where they live,send a card and letter,saying you would love to see their new place ,and is there anything they would like as a housewarming gift.
Dont give up!
It's not wrong to want to see your family!