Invasion of privacy+ bodily harm/retaliation

Looking for advice. My registered post was marked with my name+fathers name but different flat number (my neighbours flat). So the person whose flat number was written, took the post and opened it. They then tried to staple it and return it via the watchman. Postman was apparently new on the job so he didn't take the acknowledgement on the pink slip or signature of whoever collected my post. Asked him if he confirmed the name before handing over the post to the wrong people and he said he was forced by that person to give it to them and not to me. I'm pretty pissed off because the people that took the post opened it despite my name being on the post and then tried to hide their mischief by returning via watchman. I'm not sure what they gain by reading someone's post. Anyway, asked the postman to clarify it with them and ask them why they would lie about their name being on the post or why they would force him to give it to them. Things got heated and I called them (the people who took my post) out on purposefully doing this and we both hurled some abuses at each other but the wife of the man who took the letter lunged at me and beat me up (I'm a lady). My mother and father were standing next to me. I was pushed against the wall and my head got hurt and she tore my clothes. Seeing that I was in danger, my father pushed that lady and that lady scratched him on the chin and blood was coming from my father's chin. The postman saw all this. Now that lady's father is an MLA and he is threatening my father. I'm asking what I should do now? That lady not only invaded my privacy on purpose but also beat me up. The postman and my parents are witness.