
Personally, I would put that plot on hold until they come back (if ever).
For this reason I try to spread my RP around as much as I can so I'm not locked to one specific person. Like going to work with the flu. If you have it, might as well share it!
(kidding, of course)
You can also take an example from life. I have some old high-school friends that I still keep in contact with. I haven't seen them in over a year now. That does not diminish the fun times we've had in the past does it? My life isn't perpetually on hold until I get a call from them saying "Hey, let's do dinner!"
For this reason I try to spread my RP around as much as I can so I'm not locked to one specific person. Like going to work with the flu. If you have it, might as well share it!
(kidding, of course)
You can also take an example from life. I have some old high-school friends that I still keep in contact with. I haven't seen them in over a year now. That does not diminish the fun times we've had in the past does it? My life isn't perpetually on hold until I get a call from them saying "Hey, let's do dinner!"