My suggestion to unstick those trapped in conversation would be to post something like:
[Andante's character] was about to reply, but all of a sudden the door burst open and a soldier walked inside.
"Captain, something has happened further in the tunnels, and you're needed."
With an exasperated sigh, [Andante's character] says, "I have to see to this matter. We'll talk about this later."
And she leaves the room.
-----------------------------
It doesn't change the story, and it doesn' make Andante's character do anything unrealistic, but also allows all players to continue the story.
Kir, to answer your question of: "...how would you feel if you had worked for weeks on a roleplay that you were extremely excited about and had worked very hard o, but due to circumstance, you were forced to leave for a period of time. Would you be happy if the others involved left you behind and created a twisted version of the vision you had in mind? Effectively destroying and taking away control of your creation? I think not."
You think wrong. First of all, by inviting other people to contribute to my roleplay, I am inherently giving up some of my autonomy in controlling the story. If I wanted to have ultimate control over my story, then I would've written the whole thing and it would be a fanfiction. By inviting other roleplayers, I'm saying, "Here's what I have planned, but bring your own characters and share your own ideas, and hopefully your contributions will make it even better than what I can come up with alone".
If I had left my roleplay four months ago, and haven't updated anyone on the status of my return, then I would not only expect, but I would want people to continue on without me. This "twisted" version may actually be better than what I had planned, or it may be worse. But, it would have, at least, been written. The last thing I would want is for my roleplay to die uncerimoniously for lack of my attendance. And if I came back a year down the road, and the story had been written, and it wasn't what I wanted, then I would understand and start over.
If I started a roleplay, my main goal would be for everyone to have fun. If its not being written, then no one is having fun, and my roleplay was ultimately for naught.
That's just my opinion, anyway.