Actually, Isabela does come back if your romanced her and said you'd like to go traveling with her on her ship when it's all over (you have to actually give her the ship during her quest for it to work, I think).
Also, I dunno how many of you play this on PC, but if you do you might want a script to play it in a full screen window mode... I made it for mine. It's better for alt tabbing, more stable, less screwy and whatnot, maybe you'll find it useful. You need a program called
AutoHotkey - it's free.
Once you have it downloaded, I suggest putting a shortcut to it in your Startup folder so it runs every time your computer starts. That way you never have to mess with it at all, it just runs in your tray and doesn't bother you.
Now first of all, set your Dragon Age 2 to Windowed Mode by setting it to your screen's resolution and unchecking Full Screen in your Video Options.
Anyhow, you should have a tiny little icon like so:

in your system tray once you have it running.
Right click it, go to Edit This Script. It should open up a Notepad with some AutoHotkey.ahk file. Paste this code in there:
#SingleInstance Force
#Persistent
SetTimer DragonAge2, 500
Return
DragonAge2:
WinGet IDs, List, ahk_class DragonAge2
Loop %IDs%
{
ID := IDs%A_Index%
If ID not in %Old_IDs%
{
WinActivate ahk_id %ID%
WinSet, Style, -0xC40000, A
WinMove, A, , 0, 0, 1920, 1080
;WinActivate, A
}
New_IDs .= ID ","
}
StringTrimRight Old_IDs, New_IDs, 1
New_IDs =
Return
Then do File > Save. Now, right click the

icon again and do Reload This Script.
And now, every time you run Dragon Age 2, it'll automatically set it to a frameless windowed (fake) full screen. It won't run constantly either, it's smart enough that it checks to see if the unique ID that window had when it was created is still running and if it is then it doesn't do anything. So, the next time you open it, it has a new one and it works like magic.

__
I have a ton of mods for my game already, lol...