From Summer Storm by Dana Gioia:
Why does that evening’s memory
Return with this night’s storm –
A party twenty years ago,
Its disappointment warm?
There are so many might have beens,
What ifs that won’t stay buried,
Other cities, other jobs,
Strangers we might have married.
And memory insists on pining
For places it never went,
As if life would be happier
Just by being different.
I love those last two lines. It occurs to me that much of life is, or can be, focused on that “as if” and not on what is, here, now — which can lead to a sort of nostalgia for things that never were.