Hi!

First time poster here. I'm looking for insight on how to handle suicide threats from my BPD mom. My mom and I used to be closer when I was younger. She was a helicopter mom and invaded my boundaries constantly growing up. Since I've graduated college and branched out on my own, she's slowly started unraveling since she sensed she's losing control, and her BPD has gotten progressively worse as she's aged. She used to have boyfriends/partners, but now she lives alone in the middle of nowhere and has completely isolated herself, so I do worry about her.

These descriptions might be triggering for some! Please don't continue if it might trigger!
I've started setting more boundaries with my mom this year, but as a result--I haven't been able to visit with her as much as I normally do (because every time I was considering seeing her, she called me a ****, started being verbally abusive, and basically reminded me that I shouldn't see her very often). I haven't visited my mom in about five months now whereas I used to visit her every other month (it's definitely brought me some peace not seeing her as much), and she has noticed me establishing distance lately and has clearly expressed that she's NOT HAPPY! She's threatened to "find who my therapist is and sue/call the police on them because they're ruining our family". My therapist has been so helpful and I would be furious if she somehow contacted them. I was going to drive to my mom's state to visit her for Christmas, but I got COVID and had to isolate over the holiday. (I think I subconsciously wanted to avoid her,

.) She obviously freaked out and blamed it on me.
Last month, she invited me to go on vacation with her to Mexico. But I didn't want to possibly get stranded in a foreign country with her during a pandemic, so I said no. She then threatened to commit suicide if I didn't go on vacation with her to Mexico. Every time she threatens suicide, it throws me for an emotional rollercoaster. I've been getting better at recognizing that most of it is just manipulation unfortunately, and I'm getting better at managing my reaction. I obviously didn't go to Mexico with her, but she went alone and had such a great time being pampered at a resort down there that she decided she wants to move there. She told me that she wants to sell her things, move to Mexico, spend all her money, and then "drive to a funeral home and shoot herself in the head in front of the funeral home". It was honestly traumatizing to hear this information. I was more depressed than usual for a couple days after she told me this. But she was telling me her suicide plan as if it was funny/exciting. It was bizarre and I'm inclined to believe it on some level.
This weekend, I was planning to visit her for about five days and I am really dreading it. But I haven't seen her in five months and used to visit with her a lot more frequently. I honestly feel like my life has gotten harder with her since I've started establishing boundaries and creating a distance.
I was on the phone with her this evening because I was telling her that I'm planning to drive to her house on New Years Day since I've not recovered from COVID yet (kind of true--I'm just tired and don't have it in me to see her yet). She was upset because she wants me to leave early tomorrow morning. I told her again that I am going to leave New Years Day. She absolutely lost it and told me that "I don't care about her" and she started crying and ranting about how no one talks to her anymore, and told me not to worry about her because she's "going to buy a gun and shoot herself". I told her that I was going to call the police to do a wellness check if she's serious about suicide, and then I told her that I can't listen to her ranting and am going to hang up. Am I supposed to just sit there and listen to her rant in pure agony? I don't have unlimited empathy for her and it's extremely draining for me to hear.
I'm worried about her, but I worry that calling the police to do a wellness check on her might escalate things. I called her back a little later and she assured me that she's "not going to kill herself tonight but she doesn't want to live and she might at some point". She then sent me about 50 text messages in the span of 10 minutes telling me to "call her right now" over and over again.
How do you deal with a future suicidal threat? Should I just call for a wellness check? I'm dreading this visit. My therapist says five days is far too long to spend with her, which is probably true. I'm usually depressed for days after visiting my mother if her antics are high during our visit. Earlier this year, we had a screaming match and she tried to stab me with a pool cue. I was emotionally exhausted for days after that fight, and I don't want to continue on like this. I can say that her behavior is much more tolerable and she can be somewhat pleasant to be around when I walk on egg shells and try to appease her (which I don't want to do anymore). But when I set boundaries and protect myself, she is an absolute nightmare.
I reached out to my grandma today to tell her what my mother told me about shooting herself in front of a funeral home, but I don't know if I should have shared that. I just want someone else close to her to know that she needs serious help. Any advice would be appreciated! Thank you!