Just read this. Extremely well written story, but massively depressing.
This isn't a version of Elsa that I can't accept. She strikes me as someone with massive willpower. I think she'd make it her mission in life to protect Anna... especially from this kind of pain, even if it meant she had to suffer through her own depression. She'd find a way to get help and get better, or at least control it's effects. Maybe I am just too literal in how I think she would behave.