You never actually become anything for very long. Sure, you seem to go through periods of agitation and tension, but with practice there are periods of joy and humour – and as you get more skilled in attending to the mind, the habit of holding on to particular states loosens up. You find yourself identifying with this or that state less and less; and that reduces the stress and turmoil.
Seen like this, human life is a great opportunity. We can always act skilfully
and cultivate the mind; we can always move towards goodness, happiness and liberation.
Ajahn Sucitto, Kamma and non Kamma
Mindfulbalance 
I grew up with a slight variation on this: Nothing lasts forever. No matter what went wrong in life, whether it was a broken vase or a relationship, my late mother would give a benign look and say: “Alles is vergankelijk”, (dutch, literally: everything is transient”. As she lived through Japanese concentration camp, she had a first hand experience at the ephemeral nature of life. I have lived by this wisdom and it makes change so much easier to live with.
And it’s good that things change. Everything is emptiness. And geneticfractals; I like the saying you have used in Dutch. It’s true: “Alles is vergankelijk”