I'd like to get away from earth awhile And then come back to it and begin over.
The speaker transitions to the idea that going back to his childhood is an escape. He wants to take a vacation from life.
Whether it's a vacation from adult life with responsibilities or a vacation from the world of the living, we don't know.
The idea to take away is that he wants a new beginning. He still enjoys life's pleasures, and he doesn't want to die. But he doesn't want to be where he is now.
May no fate willfully misunderstand me And half grant what I wish and snatch me away Not to return. Earth's the right place for love: I don't know where it's likely to go better.
The speaker seems to make the following disclaimer: "If any deity, higher power, etc. heard me wish for a break from life, please don't take away my life without ensuring the safe return after an agreed upon time."
Just in case his dreary outlook on life is a phase, the speaker says to himself that he has no desire to make his vacation from life permanent.
His reason is that he is a lover of life. Anyone who appreciates the sway of trees in the chilling wind loves life.
For the speaker, love is a worldly idea.
"It's" (meaning love) worldly to him, because the world is all he knows.
He recognizes that the world you know is better than an imagined one.