D-Day in Inveraray

I joined a small group of local people on the green this evening to pay my respects to those who gave their lives for our country.

I'm really not sure how they did that.
I've heard politicians saying "thank you" all day on the television. 
But "thank you" really doesn't cut it, not even close.
How do you thank someone for giving up their life, for sacrificing everything they could ever have achieved....relationships, children, grandchildren, a career?
How?

I really haven't a clue.

Thank you.