Just remember, feelings aren't always logical, so they can't always be explained. Who knows when someone will fall in love, or when they will feel jealous and insecure. The best you can do is acknowledge their feelings and then move forward.
As far as I know, nothing has technically changed for the moment. But you might want to have another three-person sit-down to give the girlfriend a chance to state whatever her needs might be, and to see what can be negotiated.
I think she was just reacting to the hunting trip because she was extra emotional. That's my hypothesis anyway. Something has changed, if she is now in love. Maybe she just sees change in the world around her because something changed within herself internally? It's a thought.
You'll probably do fine as long as you move forward in little steps. Keep us posted on how things are going.
Love means never having to say, "Put down that meat cleaver!"