If you get it in your mind that the relationship is currently over. You can't go back in time, though you probably wish you could. Concentrate on what is going on now.

如果你意识到你们的关系已经完全结束了，尽管你奢望时光能够倒流，一切却再也无法回到过去，那么就专注于眼前吧。

youdao

I've kept myself numb for so long that now I actually want to feel something and I can't because no matter where I go, no matter what I do, I always end up back here with you.

很长时间以来，我一直让自己处于麻木当中，现在，我真的希望感觉到什么，可我不能，因为不管我身处何处，不管我在做什么，我总会回到这里和你在一起。

youdao

And what we can't afford right now is to go back to the same ideas that created this mess in the first place.

而我们现在所不能接受的就是重回一开始就导致这个乱摊子的老路上去。

youdao

But I can't go back to what it was like in the early days, just like you can't go back to what it was like to be four or three.

但再早之前的事情就记不得了，就像你想不起你三四岁时候的事情一样。

耶鲁公开课 - 死亡课程节选

And what we can't do now is go back to the policies that got us into so many of the problems that we've been dealing with in the first place.

CNN: Obama adds politics to women's forum

We can't go back on what makes America the great country that it is.

NPR: Patrick Murphy: From Iraq War to Congress

We can't go back to what got us into this mess.

WHITEHOUSE: Remarks by the President and Vice President in Dayton, OH