How to get divorce if wife does not grant it?

I have been married to a Russian under the Special Marriage Act 1954 since 2010. We have a 12-year-old daughter. All these years the marriage was nominal, we had almost no sexual relations, she left me for six months every year. In 2017 she had affair with another man. In of 2019 she said she wanted to become a nun and went to a monastery in Thailand. After this she left for Russia and returned to India two years later and settled my second house. I filed for divorce when she was in Russia, now the case is going more than 2 years. We have not lived together for more than three years. She changed don’t want to give divorce because she doesn’t want to lose her OCI card. She disturb us a lot, spreads rumors, spoils my reputation, insults me. I want to marry again but my lawyer says we have to withdraw the divorce case, because in response she filed for a huge amount for her maintenance. He says that we have no proofs of her misconducts, and we can get obligation to pay her large sums.