Don't lose heart.

别灰心。

Don't lose heart. Things will get better soon.

别灰心。情况很快就会好转的。

I hope so.

但愿如此吧。

Remember that you did the best you could at the time.

记住，当时你已经尽力做到最好了。

Remember that you did the best you could at the time.

记住，当时你已经尽力做到最好了。

Yes, I have no further regrets.

是啊，我没有什么遗憾了。