First time poster - Really struggling with jealousy

Bit of background. My wife and I were both raised in a very high control religious group (a cult basically) which we managed to seperate from about a year and a half ago. We have been happily married for 12 years and are each others only sexual partners but both agreed we wanted to put other options on the table in terms of relationships. We have no desire to break up and love each other very much but felt it was important we each be allowed to experience our sexuality in a way that was not allowed before. About 4 months ago my wife formed a friendship online with another man which gradually developed into a deeper relationship. He lives outside the country but she decided to meet with him, a decision which I supported. The past couple months have been difficult at times with this trip looming on the horizon, but I got to a place where I felt pretty good about it. My wife has been incredibly supportive and patient with all of my fears and insecurities. But now her trip has arrived. She's actually out of the country right now, and long story short, I'm kind of a mess. I have work and kids to focus on so that helps, but I just can't get away from my own thoughts. My rational mind is totally fine with what she's doing. I want her to have this and to experience both the travel and a new relationship, but emotionally I'm having trouble keeping my shit together. My brain is torturing me. Everytime I talk to her or text I imagine this dude right there with her and it's really fucking with me. Like it's making me physically sick almost. I know the option is on the table for me as well, but I just really don't feel like dating. Some kind of organic relationship like my wife has, maybe, but I can't see myself actively seeking one out. And I'm ok with that. I accept that I might be wired more for monogomous relationships. I'm not going to deny my wife what she needs to feel like a complete person just because I'm different. I know she still loves me and that nothing changes between us. I guess maybe it's a learning process. Not sure what I'm looking for - advice, experiences, reassurance. Maybe I'm just venting.

TL:DR; I'm not sure where I'm personally at with non-monogamy, but my wife is currently out of the country with another man and I'm kind of messed up about it.