I feel your pain! My eldest son lives in the US and because they now have school-age children we and they have to fly at holiday times, which is expensive.
My other son lives in London, near Heathrow, and the flight prices from where I am in Scotland are preposterous! Only one airline flies to LHR from here and often a one way ticket is £250+. The minimum cost now seems to be £82, usually flying at the crack of dawn or the last flight of the day.
We did get lucky when his first child was born. I had a quick look online at about 11am on the Sunday morning and saw flights for £40. We were showered, dressed, packed and checked in at the airport by 1pm!