HOW CAN I HELP MY MOM. Pls help!!

So my mom has battled cancer for a year now. She had a double mastectomy and faces heavy depression. She also had lots of pills described for her but she is very sensitive to medication and lots of side affects that usually wouldn’t effect people, effect her. She also went MIA on our entire family and is afraid of talking to them and is tired of hearing “your a fighter” “ stay strong” etc. she is dating someone who I believe is very toxic for her and they have been on and off for 7 years. They both drink heavy and are physical with each other. It is on both ends however he lives her and wants to help her. Last night it was my brothers 20th birthday my mom got home and was very upset about some comedian. She said she put headphones in and stayed. I heard from someone working there that when she got there she seemed under the influence already. My brother had a surprise party Nd all of a sudden my mom and her boyfriend were fighting and my brother needed to step in. Apparently she was swinging at him. Not sure what is really true. Then everything seemed fine until my moms boyfriend open the window and said she took a whole bunch of pills. We run inside and I see my mom and her face is swollen and her mouth is full of blood. I asked her if her bf hit her and she nodded. I asked her if she tried taking pills and said no. No one is quite sure what is true. My sister in law and her two friends sat w her in her closet and talked to her I walked away and went back outside to where my brothers friends were and realized my brother was gone but he needed to step away from the situation completely. I sat with my mom holding her and she was having panic attacks. (My best friend has panic attacks and I tried everything I do with my best friend with my mom but it was not working) my My mom and her bf ended up sleeping in different rooms and the night was fine. In the morning my brothee wakes me up and says that we should leave. I pack a small bag and take a quick shower and my mom is yelling saying how my brother is a asshole because he didn’t acknowledge his cake (he did btw) and how he had all his friends over and they all were drinking (when she helped plan it) me and my brother left to my dads and my mom calls telling us we need to clean our rooms and get home. I asked her if she knew what happened and she screamed at me she wish she did kill her self and hung up me and my brother need help with what to do. Pills are a bad idea and I’m scared to send her away. She is afraid to fight and afraid of people calling her crazy. She denied what happened last night when asked by her father. And will say what she want so that it is in her favor . She needs help I want to get my mom back. Depression is truly something hard and dark . Pls pls pls help us I am so lost on what to do at this point