I feel your pain, same thing happens to me and also on the imperial counterparts...
I have learnt a few things about it tho, firstly, it happens when the ship you are in goes into warp and my guess is it has something to do with the gfx/sound fx causing a dc, seems to happen to loads of people, i think it is a combo or the os/windowed(fullscreen)/gfx drivers
I have found 2 ways to deal with this....
1) you know when it is going to happen, so warn your FP grp u will dc and tell them to finish the convo. when youl log back in, once they have finished convo, you will automatically proceed to the next stage even if you didnt finish it, as long as the others have
2) seems to work half the time and I am assuming you are running in windowed mode probably fullscreen.....hit your windows key to bring up your start menu or if you have another program alt-tan to it, seems if swtor is not the focus window, it doesnt always crash
