Can't contact the girl who chose someone else over me.

I have tried everything, and there's only one solution left I haven't done. I don't think it's right necessarily but, I'm running out of options and I can't move on. When my best friend was in a similar situation like this he convinced me to tell his ex that he was feeling depressed and I was concerned for his safety, he wasn't, to see is his ex still cared for him. It seems sleezy but maybe trying that with this girl would be the best way to understand what she's thinking cutting all contact. I don't know what to do, I can't move on without comming to an understanding.