Need help to convince my wife to do it again after doing it once!!!

Hello my name is Zafin. And I'm married to my beautiful wife for the last 7 months. We are both from Bangladesh. As you might already guessed I am a cuckold and I love/enjoy watching my wife having sex with another man in front of me. I'm so hooked on the idea of watching her getting penetrated by other men and making her wear the sluttiest dress. I already have shared my fantasy with her way before and she knows about it. before our marriage we've talked about this and she agreed to do it once. We had MMF threesome with a guy we found online. That time it wasn't so serious and we thought we would just do it once but after that day the way I found pleasure was so much that words can't express. It was the best day of my life and I thought about doing it again and again and again. The problems started after doing the MMF., as she was completely okay with doing it and didn't say NO even once I thought she'd be willing to to it again but despite bringing the topic over and over and ensuring her that I'm completely fine with doing it she always turns me down and she even talked about ending the relationship when I was about to persuade her for another cuckold/threesome session. Idk what went wrong and don't misunderstand me, I love my wife a lot and I'd do anything for her and I won't let any harm come near her as long as I'm alive. But a men has needs too. I've tried many times communicating with her about this issue but she asked to not to talk about it again if I want her in my life. Now if I talk about her a little bit, I know she loves to wear dresses that slightly uncovers her skin and she loves to show of her asset and also when we had threesome she was so into it and she often talks about other guys when we have sex. During roleplay we often do the stranger play and etc and it turns her on so much. As from her side, she's okay with me fantasizing her with other men and I can talk about it but she won't do it in real. it's a very frustrating situation for me and I can't help but wanting her to be a slutwife, I would do anything in my hand to make the day come into reality ASAP. Is there any chance? I'm in desperate need. I hope I'll get a proper solution on how can I turn my wife to become a hotwife