Anything I could do without, but it is can not do without you! ——这是个错句。

错误在于：it is 多余，删去。或者它是 I 的误拼。改为：

Anything I could do without, but （I）can not do without you! 

这是个并列句，第一分句为了强调，把 without 后面的 anything 提前了。正常表达是：

I could do without anything, but I can not do without you!

我没有什么都行，但不能没有你！（没有你就行不通）

句子的难点是：do without sth. 意思是：没有什么也行。

If you do without something you need, want, or usually have, you are able to survive, continue, or succeed although you do not have it. 没有…也行