I didn't expect this get so sad. I don't mind it per se, but the way it's being done: that lame love-rival and Saki having had a sad previous love story which suddenly makes her all passive when she was actively courting before, isn't giving me high hopes for a great story going forward.
And the way the mangaka changed the story from the unusual and very interesting "Saki is courting timid Onee-chan." To the insipid "Onee-chan is overcoming her timidity on her own because she's a light-haired girl and claims passive Saki for her bride." is like throwing away a perfectly prepared Angus beef burger with the works on a nice and crispy bun and going to Mc Donalds instead.