Constant depression and negative behavio

My mother has always been a difficult person to deal with. She isn't very affectionate from the start. She doesn't have social circle or any friends. She never gel with people and often ends up having conflicts when we introduce her to someone to make friends. She has been divorced from my dad due to a bad marriage and domestic voilence at the age of 36. She herself had a small relationship a few years ago with a man and ended on abusive terms with him. This ended a couple of years ago. Off lately her behavior has been extremely negative and loud. She creates a negative scene for reasons as small as she missed to watch her daily soap cos she was cooking. She would go on and on and make me and my sister feel awful about it. She would not live in a separate room n sleeps in a folding bed in our room though ours is a big 3 bed room house. She would sleep most times and keep herdelf and home dirty. Please suggest what to do. It won't be easy to get her to meet a doctor for this situation.