Um, yeah. No. Ignore, block, get a restraining order. There's not even a hint of remorse. She needs a wake-up call more than anything or she might end up cheating on the wrong person with the wrong person and someone dies.
Being the third wheel around two people so obviously in love with each other and don't notice or interact with you is the most awkward feeling in the world.
I don't remember Nodoka scoring the most points. Of course that could have happened over a year. It will be interesting to reread once it's all finished.