I found the best way was somehow tell her that she can ...... with other men.
It's a difficult conversation, but if you explain that you do love her loads, and you do not want to ...... with other men, that offer of freedom will stay in her mind.
She may flatly refuse, she may be a bit angry with you, but you will get through it, and it's worth it.
I did the same with my wife many years back, we had an uncomfortable few months, but that's the price you have to pay I guess.
My wife ended up ...... with 5 different men, it was fantastic!.
We are very happy, and still going strong after 26 years, even though she lost all body confidence a few years back, and no matter how I nudged her, I couldn't persued her to enjoy other men again, and it's been many frustrating years wishing for the excitement of other men fucking my wife again.
Out of the blue, she sent me the attached photo whilst I was in work yesterday, with a text saying she's done something that she hopes will surprise me in a good way.
Shes in the process of signing back into the meet site we used, and although just looking, she says if she sees a guy that makes her go 'ooooooh', she will just let it take it's natural course.
This wouldn't have happened if I hadn't constantly reminded her of her freedom, it's been a frustrating few years, but I'm on cloud nine as my wife is going back online because she wants to be fucked by other men again, and she really is going to start getting fucked again.
The pic she sent means so much more now, because I know other men are going to enjoy fucking what's in that picture!