我放弃你不是因为不爱你，而是因为想让你获得幸福。我没能力让你幸福，所以才这样做。英文怎样说？

It's not because I don't love you so I gave you up, it's because I want you to be happy. I'm not able to make you happy, so I had to do this...

The reason why I left you was not that I didn't love you, but that I wanted to make you happy. I was not able to give you a happy life, and that was why I did this.

I leave you,its not because i dont love you,but manage to achieve happiness for you.I have no ability of making you happy,it is why i do so.

I gave up not because you do not love you, but because the want you to achieve happiness. I can not let you happiness, so do so.

最简单可以翻译成:I leave you alone because i love you.I have no power to make you happy so i gone.