I'm feeling a bit the same way, just had text from son, my grandson is off school sick and he's got to take time off work to look after him (again). If I lived nearer I could have gone and helped. It's frustrating that distance prevents that.
Pick up the phone and call your son. I use a TALK HOME (premium) card to make calls to my brother in Eire.It is only 5 pounds and can be bought in some phone shops. You scratch off a part of the card to reveal a pin number, then you have one month's usage.It will save you money on overseas calls.
Have a look at www.voipdiscount.com I have used it for some years now. It costs me 5 cents for an unlimited call to anywhere in the world. I load €12 euros which gives you 120 free days then you can either load more money or use up the balance at higher rates, then reload another €12. Once you have made the call on your computer you take it on your household phone.
You have my sympathies as I think I know exactly how you might be feeling. My remaining relatives live in Australia and as I am the baby of the family at 67 both are often suffering from one or two problems associated with their age. My brother had major heart surgery last year and my sister had both breasts removed and I felt helpless here as I had health problems of my own to resolve. When I return East later this year I will very quickly be making a beeline for OZ even although I know I will be 10 hours on a bus when I do get there. Phone calls are all well and can help but it is still not being there and being able to give him that important cuddle.