I know plenty of people who get emotional support from their friends rather than their lover/spouse.
This is a case where she considers the emotional support friend to be a romantic rival, though. There's an issue with her believing she understands Asahi's feelings better than Asahi herself, even if it's presented as true in the text, but being insecure to the tune of feeling second best isn't a good foundation at all. I think she was pretty mature to walk away.