Take her out of the equation. Would you go by yourself on this trip if you could? Is it something you're still interested in?
If yes, then can you enjoy it with her if there's no reconnection? If it's just a shared trip that doesn't change anything?
I think if you can do that with no expectations, plus handle any potential fallout, you should go. If you think that it might turn into Chernobyl, perhaps not.
