I think the actual quote is "The key to happiness is NOT having what you want, but wanting what you have"
Really, If you gave me a bundle of money I could go online and in real life and buy a bunch of STUFF and I would enjoy the trip and the decorating, but unless I LOVE those things and not always want more what would it matter.
I try to remember this when I am coveting my neighbors pool or a friends car. I remember how it felt to pay off my truck and how I stared at that final statement that said ZERO. I remember that it did not get 'old' by accident it got worn by use. my use, it has carried my family safely many miles. The sofa I am sitting on is over 40 years old and still going strong. It needs a bit of an 'update', but my grandmother held me as a sleeping infant on this very sofa. My father and his sister bought it with LOVE, it was worn by love and reupholstered in the late eighties with love. I am still wondering what my father was thinking when he chose THIS fabric, but there is more LOVE in this sofa than I could get out of a brand new one. When we moved it decidely heavy self into the new house I was momentarily wishing for a new 'lighter' sofa, but then I reminded myself WOOD, real wood is heavy!
So today love the things you have. It doesn't mean give up on having something you dream of, but loving the moment. Go for it. Be grateful today for all you have, instead of bemoaning all you do not.
The photo is of my now deceased dog, Benny Wenny Super Poodle, cradling a friends kiddo in grandma's chair! We still call that chair "ben's chair". He was a rescue, too!