No it’s something else...Yang suffers mostly from abandonment at early childhood primarily when Summer rose disappeared and it didn’t help that her father shut down emotionally and was barely there to spend time with her, forcing her to mature faster having to help raise Ruby. When she discovered Raven existed it only deepened a sense that people leave because she means nothing to them, Blake having fled after the fall of beacon destroyed her spirit pretty much the worst possible week happens to yang:being framed, 2 friends dead, one dragged back home probably to never be seen again and having her arm amputated, but that was not what broke her. She trusted Blake, fought for her and told her so much about herself and Blake...ran. She was abandoned again and Blake may have had a good reason she should have talked to yang, but she didn’t like she didn’t matter that much. And in the song ‘all that matters’ is Yangs heartbreak and resentment “the only thing I can count on is that I can’t count on you.” Pretty much sums up about how hurt she is