What is meant by"O sweet Oliver!O brave Oliver!Leave me not behind thee:but,Wind away,Begone, I say,I will not to wedding with thee." (Touchstone, At the end of Act III Scene III)
As I understand it, Touchstone sings this particular song just because it was a popular song from those times. He was clearly never going to marry Oliver so he's not really singing it meaning that he had been thinking of it.
So why is he singing at all? I think that he is singing because that is kind of his nature -- he is a clown. He is all happy here because he is not getting married. You would think that would not be the case.
He wants to get married, but he also wants his marriage to possibly be invalid so he can more easily break it off and find a "better" wife. In other words, he is strange and so it makes sense for him to sing a nonsense song.
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