I have a daughter in the southern part of the province, and we are in the northern part of BC. I just googled the distance, and it is very similar from London to Rome, over 1000 km, plus a ferry.
We facetime several times a week, and I manage to see her about 3 times a year. It's about a 2 hour flight for me, or 2 days driving, which we usually do in the summer. The grandchildren know us just as well as their other grandparents, and receive us with open arms when we visit. I also send little packages to the GC with candies, colouring books, etc., just as I give little gifts to the CG I have in town still.
You can make it work to have a good relationship with them, and have lovely visits to look forward to.