Hi Sookie
I sympathise with you. Gatwick is an absolute nightmare to get to. Newcastle and/or Leeds Bradford are my nearest airports.
Trains, when they run, or not on strike, can be a nightmare, and I have no intention of dragging my luggage across London on tubes, etc.
National Express is an option if you are prepared to spend 8-9 hours in a coach.
Another option is to fly to Heathrow and take the Heathrow/Gatwick National Express coach. When you come out of T5 the coach stops are very easy to find.
Some tours go from Newcastle but often travel at ungodly times on cheap airlines.
I have looked at these options several times, but have reluctantly come to the conclusion that if it doesn’t go from Heathrow, then I don’t go either.
Hope some of this helps,
Sylvia