Sometimes you can get struck by the transient nature of everything. One day all life and moments of love will end. When stricken, I think of this poem:

Do Not Go Gentle Into That Good Night

Do not go gentle into that good night,
Old age should burn and rave at close of day;
Rage, rage against the dying of the light.

Though wise men at their end know dark is right,
Because their words had forked no lightning they
Do not go gentle into that good night.

Good men, the last wave by, crying how bright
Their frail deeds might have danced in a green bay,
Rage, rage against the dying of the light.

Wild men who caught and sang the sun in flight,
And learn, too late, they grieved it on its way,
Do not go gentle into that good night.

Grave men, near death, who see with blinding sight
Blind eyes could blaze like meteors and be gay,
Rage, rage against the dying of the light.

And you, my father, there on the sad height,
Curse, bless, me now with your fierce tears, I pray.
Do not go gentle into that good night.
Rage, rage against the dying of the light.

– Dylan Thomas

As humans we are at odds with things because of our seeming uniqueness, making us joyful while in love and life, yet it is bittersweet at times because we know that one day it will all end when we die. Therefore, we should fight death to the end in order to better appreciate the love and good things in life.