"Finally, I'll have my old room back."
There are parts of the world where people probably think primogeniture is a fancy way of grilling sausage (or that it's a word I just made up to sound fancy), but for Elsa, it was a career and a lifestyle all wrapped up into one and thrust into her lap within seconds of her royal mother making the king's icicle start to drip, if you catch my (snow)drift. I do not apologize for either of those puns (because I'm cold-hearted ... BAM!). Elsa had no brothers, so as the eldest, she would one day rule the kingdom of Arendelle.
Thus becoming part of the ice-tablishment. (Sorry. last one, I swear.)
That is an excessive amount of pressure to place on a child who's barely old enough to color inside the lines, but she could at least hope for a baby brother to inherit the pressure ... right up until her parents' sudden deaths. Basically, she becomes an orphan and has her entire life decided for her, all while she's still a teenager. It's actually shocking that her powers didn't manifest as goth poetry.
Once she grows up, Elsa has no real positive memories of her parents, and for good reason. Her ice powers / depression freaked them right the hell out, so they locked her away. Now she has to follow in their footsteps, put on a happy face for the people who admired and respected those parents she barely knew, and rule a damned country when she hasn't left her bedroom in years.