It's hard when we empathize so much to these characters Jane Austen created, isn't it? They are so real that it can be hard to imagine they wouldn't feel or act as we would when we see them in similar circumstances.

I don't see Elinor as having a problem with or disliking keeping her own emotions under good regulation, though. She keeps her emotions under good regulation because she wants to. It is true that she doesn't wish to cause pain or grief to her mother and Marianne, but she also knows that they would be only too ready to hear about her problems at any time.

Edward does not strike me as being unwilling to listen to Elinor at any time, nor do I think she will hide her emotions from him once they are married. But, before he could declare himself and his feelings for her, she was wise not to show the extent of what she was feeling for him because it would have put all of them in an awkward position. In fact, I think that if anything, it would have scared Edward away, for he would have realized they were both getting in over their heads, so to speak.

IMO, there will not be as many unexpressed issues in Elinor's future as there have been in this extraordinary two-year slice of her life. She will have a sympathetic husband, a dear sister living nearby, and a brother-in-law who also understands her very well. There is little need for secrecy any more among any of them as there has been. On the other hand, being the parson's wife, it is good that Elinor can avoid speaking her mind, as I'm sure the occasions will arise in their parish from time to time where that will be a valuable skill!