Need help with mum...

So theres this guy who was our neighbour at our old house and we knew him for like 7 years, and we are pretty close with him. then one day I come home from holidays to go to my mums (last week) and I say something about him and she says oh we can’t go over there anymore he was cheating on me (with this girl who was living with him who we all really liked) and im like wtf I didnt know you were together… the next day shes crying her eyes out and explaining stuff and I got pretty confused.. shes been depressed for days now. She drinks more and slightly overdoses on these sleeping pills and then goes out to ‘clear her head’. she went out afew hours ago and I’ve called her about 3 times 30 mins apart and she said that she’ll be home in about 5 minutes. But shes stopped picking up and its been an hour since I called her last. erlier tonight she told me to send these random texts to him and im like ok.. and I get a text back from the girl that the neighbour was with (from the neighbours mobile) and its this whole long text explaining her story, like the neighbour only had a sex relationship with my mum and then found the other woman for a senciere woman.. and near the end it says my mum went over there the other day and destroyed their things and hit the girl, and if I keep texting them she’ll call the police. But yesterday and thismorning the neighbour guy was asking my mum to move in with him and stuff. I really dont want to show the text to my mum.. I think she’ll do something stupid.. and im really worried about her not answering her phone. I am soo messed up. I d k what to do.. Ideas?