At the wedding party, the bride and the bridegroom expressed that they would live in harmony and mutual respect and grow old together.

婚礼上，新娘和新郎表示要互敬互爱，白头偕老。

《新英汉大辞典》

I'm sure they'll be very happy and grow old together.

他们肯定会幸福美满，白头偕老。

youdao

Is this, he wondered, what it means to grow old together?

他思忖着，这是不是就是白头偕老？

youdao

And perhaps we will grow old together.

NEWYORKER: While the Women Are Sleeping

So tell my superman any time he needs his ego stroked all he has to do is say those 3 little words and let me know he is ready to give up caring about what the world thinks and explore a new fronteer in what we can build together because I dont want to grow old without him.

FORBES: Paul Allen and Rodney Dangerfield: Neither Got Enough Respect.