The thing is, aside from some exeptions, you take them with you because you are in a similar bad situation. This does *not* change, just because she tells you that she is a Sharran.
I think it does ...
I feel no reason to keep helping her, i dont want to be even seen with her, and i dont feel either comfortable or safe with her chilling in my camp while i sleep there.
That is all reasons my character needs to want her gone.
We may get the option *after* the tadpole situation is solved. But it makes little sense before.
I strongly disagee ...
But even if (and that alone is a big if) that would be true, who said i have to play reasonable character? :P
The exeption would be if a companion attacks or betray the group.
And my character see this as betrayal. :P
not letting them turn into an Illithid is more important than to not travel with someone you do not like.
I believe that prioritizing importance of stuff for my character should be under my own direction.
That all said:
Especialy since the game clearly is prepared for option that she will actually not be part of my party ... since, as stated before, multiple times ...
- you either dont have to recruit her in the first place ...
yes im aware she will come back over and over, that is not the point here ... as she is coming back, she is coming back as an NPC, not as member of my party ... thats called difference- or can drive her out by smashing her head with your weapon/spell enough times so she finaly starts to hate you.
So the only thing im asking about is a button that saves me need to go out-of-character and keep killing her until she finaly leaves.
Is that really too much to ask?

---
Sigh ... here we go again.
Ok, i will repeat it once more for you ... but PLEASE at least try to pretend you read it.
A LOT of D&D table games are modules with pre-determined targets and artifacts you need to get.
As stated before, multiple times ... she can leave your camp on her own will ... so (logicaly) the game is prepared for option that she is not in your party and yet still alive.
The only thing that is missing here (and what im asking here) is button that would throw her out, aka cause exactly same situation, initiated on your rather than her side.
As for what consequences have game prepared? Even if that would mean Game Over ... not important here.
Its also (and that was asweel stated before) not Game Over ... next morning you simply wake up and as Narator puts it:
"
You notices there is something in your bag ... the box that Shadowheart were holding."
BTW, exactly the same scene plays when she die.
Should she then track you down in order to get her box back?
Sure, whatever ... again, not important here.
The important part is making her "not member of your party" ... what will she do afterwards, is none of your business.
And you can only keep insisting you are role-playing your character by ignoring the thing the DM is blatantly telling you to grab and that you need for so long.
Except i didnt said a single word about "the thing" ...
This is NOT topic about the stupid box!
At some point either the DM quits, you get kicked from the table
Quite honestly ...
If i would play with DM that would force NPC as Shadowheart to my group ... and i can elaborate futher if you need it.
Then i would probably quit much sooner and simply kill her, no matter how out-of-mine-character that would be.
And just for the record ...
If your DM is railroading you this much ... he is not very good DM imho. :-/
You can complain that it breaks your immersion all you like but something along these lines happens in most DND games...
People killing each other every day ... therefore it also happens a lot ...
That dont makes it right tho.
you have to get the plot device the story depends on.
We are talking here about character, not device.
Yes, i know im repeating it again as reaction to single post ... but you repeated it first.
Also if the DM presents your party with a guide it is generally not a good idea to insist of kicking the guide from the party and the DM absolutely CAN tell you that the guide will not give up the plot device without a fight...
Cute ... but Shadowheart is not our guide.
and you can choose to kill the guide but believe me...that will make your session MUCH harder at a table
I did ...
And it did not.
On the contrary, after we were done with our adventure, DM revealed us that his original plan was for our guide to actually sacrifice us and run with treasure himself.
I gues it depends on your DM, i had great one. ^_^
DMs insist you grab a certain NPC when said NPC is crucial to giving you vital info as you go along and you'll depend on many more dice rolls to survive without the guide...
Again, that is cute in general ...
But we both know that this is not Shadowheart case ...
Since she ... and please focus now: can - leave - your - party
Therefore: she - cannot - be - indispensable
Capish?