I was a virgin

I wasn't a virgin when my wife and I started dating, but she was. It was such a powerful, special feeling knowing that I was the only guy who had ever been inside her. So years later when I started fantasizing about watching her fuck other men, I had very complicated feelings about it. However, the urge only got stronger, and I started encouraging her to explore. She agreed. It took a long time for her to work up to actually fucking another man, but every step along the way was both terrifying and incredibly exciting. She'd come very close to fucking one guy on a few occasions, and the night she finally spread her legs and took his bare cock inside her was indescribable. Watching how her body moved and reacted while they fucked, knowing that I was no longer the only man who had shared this most intimate experience with her, was the most erotic moment of my life. I've gotten to watch her fuck or been in threesomes with her many times since then, and while the anxiety has faded the arousal hasn't diminished a bit. I only wish I'd given her the go ahead to do this years before.

I encourage you to consider this. The mental image of another man cumming inside your wife may be hot, but it's nothing like the real thing.