Husband has extra marital relatons, but not filing for divorce

I have been married for 20 yrs. My husband had affairs bfore marriage and relations with 2 different women since last 8 yrs. He has always been abusive, harasses, bullies and threatens me with financial and other threats. He remains out of house for 7-8 days together on pretext of work (in the same city). He is a caterer for marriages & functions. Since last about 2 yrs., he doesn't have physical relation with me. One woman's husband has filed a case against him & his wife for having extra- marital relation (in Feb, 2014). She is one of the 2 women. What I m noticing is that my husband is passing time for some unknown reason. It seems to me that he is collecting some evidences against me & preaparing some witnesses against me by giving them money and other favours. Evidences like, negligence of house, being abusive etc. He is also collecting bills etc. to show that he takes good care of us and spends money on us. He is also preparing alibies for him to show that he is good with me and my daughters and doesn't have extramarital relations. I am certain that he wants to separate from me, but why is he not filing for divorce yet, I wonder. He always tells me, when we have fights that bring proof of this and that. He hides all his financial and others things from me. I am totally financially dependent on him. I have a feeling that he wants me to file the case. Sometimes he says also that I would harass you so much that you would ask divorce yourself. And now for last about 1 yr, he denies everything he said or did. He says nothing of the sort happened or he said. What could be behind all this? I am always so worried and wonder. I have no family support either. My parents died before my marriage. Could you pls. advice me. i would be very greatful. - Lakshmi Gupta