They do not move up there because we are supposed to be caught out in the open multiple times so everyone can ridicule our choice and the LI has a more open getaway spot after we hit the full "Love" lvl of the relationship and they decide "It's Over".
I cannot stand Vivienne as I have stated above and truly I do not think I have ever despised a character from any game as much as her. With that said, during my second play-through I chose an Elf-Mage with Solas as the LI, I discovered something lovely. First off when you first meet her in her "home" I decided to have Vivienne deal with the insult in a more permanent fashion and she was all over me from that point forward. Then when I chose Knight Enchanter as my specialization I thought we were going to have another avalanche because she was squealing in delight at such a pitch Mabari were cringing everywhere. And with each decision I made her over the top bottom kissing kept getting worse.
It opened up a whole new world of what this chic is all about and I have to say, I do not hate her anymore. I despise her weakness and her ruse. She is a cruel, hateful, power hungry, ****** who wants more power so that she can make ppl suffer. There is nothing redeemable or trustworthy about her in my opinion.
I also found that as the game progresses, the more you take her out with the other party members and they get to know her, they discover what she really is as well. Solas, Cole and Vivienne has the best banter through out the game when it came to putting her in her place. And the things you find out about what she has done to obtain and maintain her lifestyle is very eye opening. It makes you understand why your dislike is so strong from the beginning. I did take her out with the party a lot more often but only because it is hilarious to watch her being called out on her BS and insulted. Watching her trying to worm her way out of Cole's honesty is some "stop in the middle of the woods and make popcorn" worthy entertainment. Party banter is highly worth recruiting her over and over.