Husband threatening to send some notice

My husband had an affair with his aunt till marriage day. After marriage, I found out. For 2 years I kept quiet and since she was still disturbing us, I informed her husband with the proof I collected. Now his aunt and mom are instigating him to divorce me. He wants me to apologise to everyone for hurting them which I’m refusing to do. Because of this, he has been constantly abusing and doing pure domestic violence (I have proof of this too). However since we actually share lot of mutual love, and it is only these 3rd parties (his mom and aunt) creating rift, I don’t wish to put any DV case etc. They are poisoning his mind completely. Whenever he abuses, I am nowadays mailing the uncle and his sons and informing that due to that lady, this much abuse is happening. So now my husband is threatening to send me a divorce notice that will ask me if I’m ready for mutual consent. I said do whatever you want, I won’t give mutual consent. So my question is: is he just threatening?