Tyre punctures, worn locking wheel nut

[Lel]

Hello
Firstly, apologies if this has been discussed elsewhere, but I have looked and can’t seem to find a similar predicament.
I have owned a 2006 xc90 for 5 years and live out in the sticks (miles of single track poorly maintained roads on a daily basis)
The car picks up punctures all the time. And I really do mean all the time. Sometimes they can be repaired, other times it’s a replacement. I have sought a lot of advice from a lot of tyre fitters and they all say the same “it’s a heavy car, and flint/stones will cause punctures.”
The tyres gave stones embedded in them within a couple of miles from new on these roads.
I’ve run with premium continental, Pirelli etc plus budget. Makes no difference in terms of picking up punctures.
Added to this, I have just picked up yet another puncture and have been told the locking wheel but is too worn and I will need to take the car to have all 4 drilled out.
It’s getting to the point that I think I may have to sell the car and get something that will be more tyre friendly
Unless anyone has any ideas? They would be gratefully received. Thank you!