For that matter, what exactly are you suggested the alternative to "All right, I'll support you!" is, when the friend is going all "I want me some succulent manflesh"?
Lmao
I think the point they're making is that maybe, just maybe, things would not have reached this stage if she had spoken her feelings before.
The two friends have been together all their lives. They're what now, 16? Plenty of time to say "You're the most important person in the universe for me, I want you to stay by my side forever!" But she never said it, she took the black-haired girl for granted... and now she's gonna learn the truth in the old saying "You snooze, you lose."