Even if she thrives, that doesn't mean it will be easy for her. She'll need to adjust before thriving. Of course, I really don't see how her new life is all that freeing since she could have done whatever she wanted at Downton and continued nursing or helping people if she really wanted to.
I certainly hope it isn't/hasn't been easy for her and that we see/hear some of the adjustment struggles. One of the reasons I'm not huge on Sybil and Branson (individually or together) is because the show hasn't shown us that any of their decisions have been hard or that they've suffered/struggled with the consequences of decisions. I mean, in a for serious way. And for all Downton's faults, it DID demonstrate this for other characters. For example, Sybil goes off to be a nurse (and nobody really gives her a hard time for it) and she has one brief dialogue with Branson where she says she's witnessed a lot of suffering, but the work is worth it and poof - that's it. Nursing is very valuable, but surely it is emotionally exhausting at times and it would have been nice to see Sybil actually struggle with seeing so much carnage or have a longer arc where she got invested in the health and recovery of a particular soldier (not in a romantic way). One thing that bothered me about her character was how sad she seemed that the war was over ("I miss the hustle and bustle" or something to that effect is what she said to Branson). Seems like a callous line for a woman who was noting how many of her dance partners were dead in episode 1 and saw Matthew suffer from paralysis. I'd have loved for her to get called out on that...As another example of lack of significant struggling, at the end of the season, they get some pushback from Lord Grantham regarding their marriage, but ultimately secure his blessing and Sybil still gets some money (which she's obviously happy about, judging by that final church scene). Mary and Edith are allowed to go to the wedding. Doesn't seem too bad to me. If I'm to get on board with Sybil/Branson next season, I'd actually like to see them struggle. Stilted, repetitive conversations in a garage didn't do it for me. And like I've said before, I *want* to like these two characters and would have loved for a legitimate conscientious objector storyline.
I wonder if one of the reasons Sybil/Branson's characterization was a fail for me was also because they have very limited interactions with anybody besides each other on screen. Mary and Matthew (for example) do have meaty scenes with other characters (Anna, Carson, Granny, Robert, Sir Richard, Isobel). They don't exist in a vacuum. Sybil and Branson seem to have spent the war working all day and then having once per episode garage dress rehearsal scenes for ultimately deciding to leave together. In my mind, it really would have helped to have had Sybil talk more with her sisters (I thought Mary spotting her and Branson together and telling her not to do anything stupid was a good scene - more of that would have been helpful) or hell, more with Isobel, who told her to go off and learn to nurse and then barely interacted with her. Similarly, while I get that Branson was geographically isolated pre-soup incident and certainly would have been ostracized post-soup incident, it would have been nice to hear more about his journalism skills (I don't think reading the newspaper counts as knowing how to write articles...) via conversations with some of the other servants.
For season 3, I'd like to see the following for Sybil/Branson (assuming the actors are up for it) but I don't hold out hope:
-some jealousy on Sybil's behalf that Mary/Matthew's wedding is getting so much positive attention...it's time for Sybil to show some realistic human failings and I think it would be very understandable that she would be happy, but jealous
-some marital tension, perhaps because Sybil wants to continue to nurse post-baby and Branson isn't keen on that. It'd also be interesting to hear what kind of reception she got from Branson's family given that his mother was evidently against the marriage...
-some real political discussions between Branson and [insert some other character, not Sybil]. Ireland vs. England, etc...Sorry, but in response to whoever said upthread that they did their best they could to show Branson's commitment to being anti-war, no I don't think they did. I think there is potential for some juicy political conversations in season 3..
-the reveal of Sybil/Branson's marriage along with the Pamuk affair and Bates trial and the Crawleys trying (but struggling) to find ways to stay strong and together in the face of so much bad press (presumably London society will mock them for allowing their youngest daughter to marry an Irish chaffeur)