If your daughter and family moved to be nearer you then the other grandparents, who currently are close, would be two hours away or is that okay as long as your needs are met!! If you're that desperate to be closer then perhaps you could consider uprooting your life and moving to the area they live in. We cannot control our adult children's lives and make choices for them, Neither should we.
Perhaps they have realised they have come to love the area they live in and have a good local support network and jobs they don't want to live. Perhaps the parents in law are not so needy so easier to live closer to!! Yes, you can be sad because your daughter led you to believe she would mover closer to you when she had children but I'm afraid people can and do change their minds. Feeling sorry for yourself will get you nowhere so just plan ahead how you can get maximum involvement with your grandchild which suits everyone.
However, I find it strange that you don't seem to care that your son has emigrated. Isn't he equally important? Home truths may not be what you want to hear but, from your post, it seems the facts nevertheless.
Do you think you know when you are going to die?
By special request, let’s discuss our favourite Classic Music and why?


- I have no grandchildren living close to me, but I have wonderful relationships with them nonetheless. One granddaughter is two and a half and lives in New Zealand, I've visited her twice and that's enough so that when we Facetime she knows me and chats away. My two grandsons (8 & 5) are two hours away and every Easter they come on holiday (without their parents) with us - we're very close. My youngest grandson (6 months) lives an hour away and we're just establishing a routine where we see him once a month. 
