Help in Classical Japanese

[kawaiiusagichan]

I found this line in a manga:

よのなかにいづら我が身のありてなし
あはれとやいはむ
あならとやいはむ

The first line probably means 'the world is big yet I have no place in it', right?

I don't know how to do the 2nd and 3rd lines. Please help! It would be best if you could do a word-by-word explanation so I could learn too. Thanks!

[A. Koba]

Oh, classical Japanese……, it’s not my cup of cake, but I’ll try.

The “Waka”, Japanese poem is from “Kokin-waka-syu”.
世の中に いづら我が身の ありてなし あはれとや言はむ あなうとや言はむ

The meanings are below:

Recent Japanese;
この世の中に、さても、この身はあってないようなもの、とすればこの身を含めた世の中全部を「いとおしい」と言おうか、「嫌なものだ」と言おうか

English;
In this world, my body (existence) is nearly nothing.
So that, I might say I feel “love” or ”hate” to this world including myself.

FYI, please check the HP below.
http://www.milord-club.com/Kokin/uta0943.htm