I'm in the same boat. It's on my mind 24/7 I really want her to enjoy other men

This craving is driving me nuts and has for quite some years. I am 47 years old and wife is 49. we have had some close encounters but that's all. She has watched a couple of guys masturbate for her on nude beach while I watched from afar. Sex after that was unreal. We have spoken about it during sex and she goes crazy and she gets soaked. She has roll played in bed talking to me about other guys and it drives me wild lol. I have offered her to be with other men while I watch but still nothing. We have been out in summer months with her wearing short skirt and no panties exposing herself to men. Once again dripping wet and we had hot sex after. Am I doing something wrong? I want to be in a cuckold relationship. What do I do?