Form 11 rule 15

My friend got married 2 years back. She was here in India an year after marriage but her husband went to US telling that he will take her in 3 months and postponed it to an year. Finally she went to US and they were normal. She then realized that he was not working and also was cheated. Family also lied that they have property but actually do not. Realizing that, she started questioning him about the property. Then he and his mother planned and sent her back to India also booking a ticket back to US. Trusting him she came to India and was shocked knowing the deceptive nature of her husband and mother-in-law. Knowing that she was cheated, her parents sent her back to US with a hope that everything gets settled. But her husband came back to India leaving her all alone. Now claiming that she raised her voice on his family, he sent a notice of divorce under form 11 rule 15 of marriage act to her. As she is still in US she will not be able to attend. Kindly suggest how to proceed and what are the consequences if she will not attend on the date.