Rockon, DBing isn't easy because we want to do what comes naturally. However, if you think about it, doing what came naturally is how you ended up where you are. So you have to think differently. DBing is counter-intuitive, and it is that counter-intuitiveness is what makes it so effective!
For instance: The natural, intuitive approach is to try to be around her as much as possible and try to communicate with her as much as possible. However, it is almost a guarantee that approach will end up driving her away faster. The counter-intuitive is to pull back completely, leave her to figure out her stuff herself, and to move forward with your own life. That is where the get a life, 180ing (self-improvements), and detachment can help so much. Because it removes the pressure and pursuit from her, and allows you to focus on yourself. Either she will get interested in the new Rockon, or she won't, but that is out of your control. Focus on what you can control.
One example that would have applied specifically to your own situation: "If I go to this party there is a chance I will see her. So instead I will send my regrets to the host and I will find something to do with one of my friends (not within the common circle). That would have been backing off and leaving her alone to figure her own stuff out. In fact, she probably would have been interested to know what you had done instead! We've seen that a lot. When you start to change your behavior she will take notice.
M(53), W(54),D(19) M-23, T-25 Bomb Drop - Dec.23, 2017 Ring and Piecing since March 2018