Gam zeh ya'avor- this too shalt pass

I have my suspicions that my dad doesn't really like me mentioning him in my blogs, which I seem to have a habit of doing occasionally, and I don't think he's quite gotten over one of my previous posts where I defamed him by calling him clumsy.So I'm going to try and not do that again.
Anyway, yesterday, after burning his hand picking up an oven tray (fresh from the oven), he told me a story which I found quite interesting. He explained to me why he doesn't let things bother him as much as they used to.
The said story was an old Jewish tale about a King who gets his minister to find him a ring that can make a happy person sad, and a sad person happy. It's not a particularly stimulating story (he found the ring without any dragon slaying or fairy princesses involved unfortunately), however, the message behind the story did make me think.
The ring in which the story refers to was engraved with the words 'this too shalt pass'.  Which, in English, basically means that anything that's been bothering you lately will eventually pass. In fact, your life will pass, and the world will continue. Just a lighthearted, uplifting story for Christmas day, then.
The phrase is meant to remind people that there is no need to feel overwhelming emotion, happy or sad, because it will always pass. Now, I like this advice, in terms of there being no point in worrying about things. But being told there's no point to feeling happy because it will pass? Not for me, thanks.
If you took this advice on board completely, what would be the point in bettering yourself or forming relationships, or steering in any way towards your own happiness, if it's going to be over? Just because there's no pleasure that can last forever, doesn't mean we shouldn't bother.
Is that just naive of me, though, to think that problems aren't worth getting sad about, but to still allow myself to feel happiness? I guess my own interpretation of this story is that the little things that we worry about don't actually matter if you look at the bigger picture and remember that whatever is going on in your life, it's only temporary. Definitely a bittersweet sentence.
However, one thing we're all guilty of is never being satisfied, constantly wanting more. I'm sure we've all experienced that feeling when everything seems to be going well, but we can't just simply be happy as there's always some insignificant little problem that we focus on, isn't there? We're never completely happy.
Well, next time you find yourself focusing on something trivial that's getting in the way of your happiness, think of this saying. And then maybe, just maybe, your focus can be on what makes you happy.
What my dad has realised, that when something good happens to him, he doesn't get too happy because the feeling won't last - and whatever it was that could have potentially made him smile in the first place, isn't permanent.
However, I think maybe he should be careful about how many philosophical stories he tells me - because things that you post on the internet do stay forever! So for those reading in 100 years time (I don't flatter myself, I don't expect it to be much above the thousands), my dad's endearing clumsiness may not have left much of an impression on earth, but it has with me [insert photo of cheese here] Well, I hope you all had a good Christmas anyway, not that it...really matters in the long run...