My 'D'F (late 70s) is an abusive, narcissistic person. He has been awful to all his children, including possible abuse towards a DD (not related to me). Also emotionally abusive to partners. My DM (late 60s) is not like this, but stayed in the marriage out of fear of other's opinions/denial etc. etc. I made peace with this a while back and only visit occasionally in order to protect myself.
DM has stopped treatment for cancer recently.
I've been sent a recording from a visiting relative during which my father tells my mother to commit suicide (giving details about methods including suggesting paracetamol and cutting wrists) or to 'accept his help' in talking to doctors (he has a science PhD so sees himself as better than an oncologist). He repeatedly suggests suicide as he hates seeing her in this position. DM doesn't want more treatment. She also can't speak well anymore, so can't even argue back now.
Is there anything I can or should do about this? I dont have anyone to ask for advice. I'm so sorry for my DM but am used to DF being like this, so it isn't that shocking for me. I'm going to try to visit her soon and will try to have a private conversation, but whenever I've attempted to get her help before she's refused. It's not impossible he'd 'help her' on her way, and while I have sympathy towards assisted suicide sometimes, this is definitely not a relationship where it should occur.