Case against my Girlfriend

My friend and his girlfriend are in relationship for a year. They didn't have s*x but however they had all other pleasures. The girl is now rejecting him saying he had blackmailed her for getting into a relationship and she do not want his relationship now. Also, she filed a complaint against him quoting that he is threatening to leak their photos in the internet and to her upcoming fiance.! Now, he wants to file a case against her saying that his love is true and he wants to marry her still. Can he file a complaint for this? Also, Can he file a complaint saying that she had cheated on him. He has some voice recordings and few pictures and some text messages as evidence. Both of them are of 21 years of age.