Dear Rai:

If your boyfriend has not displayed any violent behavior in the past, with you or with others, if he displayed lying but no violence, if I was you, I would  inform the new girlfriend as soon as possible, telling her who I am and sending her a note where I will repeat what you shared here.

It will give her the opportunity to choose better for herself and it may feel better for doing  something toward justice (preventing another human being from believing a repeat liar) following an injustice done to you, recently by the same person.

anita