Due to ill treat of my Husband

Dear Sir / Madam, This is to inform that Sapna christian married to a Hindu - Deepankar, its a inter caste marriage. We have a 4 yr old son - Mahant. Here i'm writing to get advice from the lawyers my husband was good but these days he has become very arrogant and uses abusive language and his way of behaviour towards me is very bad. He very often talks bad about me and we had a fight where in he had kicked me very badly and keeping his leg on my throat so that i can die and he also says that i'll help you to commit suicide & want to see the suffering and pain i'm going through. He hit me on my face and left a mark. Seeing this i could not keep quiet and informed my family to take me out. And till date i've not returned to my in-laws place due to his behaviour. Now since i've my son and i want my husband to give it in writing that what ever happens to me he will be held responsible. Since there is no much security in my in-laws house, i'm asking him to take a separate house wherein we can lead a peaceful life. Kindly help me or draft a letter for both of us to sign the agreement that i can be happy.