My family has always been scattered, OP. You've been lucky so far !
My parents left England with us kids , and we grew up here with no family at all. I only saw my grandmother once in all my life , and there were no phone calls or visits . Mum used to write to the family and send photographs - that was all the communication we had.
I married a serviceman and we left our home and lived all over the country, only seeing our parents once a year. Phone calls were expensive so that only happened rarely. Once again, letters were the default means of communication.
Now my son lives near me, but my daughter has moved with her husband's work, 1,000km away from us. We're lucky that we have Facetime which is great for talking to the children, and travel is comparatively cheap now. I fly to see them about once every two months , so it's not too bad.
All you can do, is to use the many communication tools that we have now. Text often, send pictures, make sure to use Facebook and Instagram to keep the communication going. It's not entirely like "being there " but it does help.