What should be my point of view About this girl?

I and a girl met in primary school, we fell in love and wanted to marry after our school and college but because we were from different Castes and she got married n I too hot married and she almost faded my memory and after about 10 long years we met by chance and after spending some time I fell in love with her again because I was alone as my marriage had broken up. She told me that I was the only one who she always loved since childhood. I later realised that she already had a bf and she kind of did these things to me, she abused me like she was talking to me while she was having sex with her bf, she later came in relationship with my best friend while she was having her husband, me, her bf in her life because of which our friendship broke. Iam not able to take this pain that Iam going through in my heart, doesn’t even feel like living. She is happy and spending time with her bf and sharing everything about me, probably she may b saying that Iam not important to her and that he is so important to her and he is influencing every decision of her like she has to take permission from him if she has to meet, or meet him and have before she has to meet me. I feel like dying because this pain is something that I cannot bear. I am feeling that Iam lost and left alone. Please help by giving it advice.