A year out and still dealing with fallout

[Before you can make things better, you have to stop making them worse...]

Hi folks,
So it's been a year since my unexBPDh had a complete psychotic breakdown, wherein he was verbally and somewhat physically abusive to me during an insane 14 day rage fest.  We are now divorced and co-parent a teen son.  It's been a year of a lot of self-growth for me, learning about my co-dependent tendencies and working on self-care.  I was under the impression that my unexBPDh had somewhat stabilized over the course of the year.  I was finally finding my feet and feeling a sense of equilibrium after a long painful year of detaching.  I keep my interactions with my ex to a minimum (lots of texts/emails) and I'm gray-rock the few times I see him.  Emotionally I have very much moved on and I have zero desire to reignite any type of relationship with him.
Today a mutual friend of ours, whom I hadn't seen for a couple of months, asked me over to her place. Apparently, she (and another friend) received visits from my ex two weeks ago that so alarmed them that they decided to contact me.  Apparently, my ex  was highly dysregulated during their visits, crying one minute, raging the next.  He is still highly fixated on me and maintains the idea that I "tortured" him during our marriage.  He said that we had no sex life for at least a decade prior to our divorce (so not true - we were regularly intimate right up until his breakdown).  He still blames me for everything that is wrong with his life.  He is balancing relationships with two women, a serious addiction to pot and experimenting with ecstasy and other drugs.  He is on the verge of being broke.
My friends are highly concerned about my physical safety (and to a lesser extent that of my son) and worry that my ex will harm me given the level of venom and hatred toward me that they witnessed in him.  They are actually worried about the women he is in relationships with too because he expressed a level of hatred toward women in general that highly alarmed them.  These friends are level-headed and not typically given to histrionics.  They felt compelled to share this information with me.
Trouble is, I have no clue what to do with it.  My interactions with my ex are so brief these days that I can't really gauge his stability.  My son reports few concerns during his overnights with my ex (although he is a typical monosyllabic teen and doesn't tend to share much emotionally overall). My son has never been a trigger for my ex.
One of my biggest difficulties has been trying to navigate this situation with my in-laws.  They finally admit that my ex was acting a little strange last year but they want to believe that this is due to a mid-life crisis and put the whole ugly episode behind them.  Their denial is deep.
Here I am - trying to detach and thinking I'm actually making good progress - and now I feel like I'm being pulled back into the murky depths of BPD again.  Do I just ignore the concerns of my friends, or relate their concerns to my in-laws, and/or keep calm and just carry on?  (Just to clarify, there was one episode in my marriage over a decade ago, where my ex in a complete rage attempted to inflict lethal harm on me.  I never witnessed this level of abuse again even during his complete dysregulation last year but I know that his capacity to seriously harm someone is possibly lurking there during an out of control rage).
I can't see the forest for the trees here so all insights are welcomed.
Warmly,
B

[Baglady]

Hi folks,
So it's been a year since my unexBPDh had a complete psychotic breakdown, wherein he was verbally and somewhat physically abusive to me during an insane 14 day rage fest.  We are now divorced and co-parent a teen son.  It's been a year of a lot of self-growth for me, learning about my co-dependent tendencies and working on self-care.  I was under the impression that my unexBPDh had somewhat stabilized over the course of the year.  I was finally finding my feet and feeling a sense of equilibrium after a long painful year of detaching.  I keep my interactions with my ex to a minimum (lots of texts/emails) and I'm gray-rock the few times I see him.  Emotionally I have very much moved on and I have zero desire to reignite any type of relationship with him.
Today a mutual friend of ours, whom I hadn't seen for a couple of months, asked me over to her place. Apparently, she (and another friend) received visits from my ex two weeks ago that so alarmed them that they decided to contact me.  Apparently, my ex  was highly dysregulated during their visits, crying one minute, raging the next.  He is still highly fixated on me and maintains the idea that I "tortured" him during our marriage.  He said that we had no sex life for at least a decade prior to our divorce (so not true - we were regularly intimate right up until his breakdown).  He still blames me for everything that is wrong with his life.  He is balancing relationships with two women, a serious addiction to pot and experimenting with ecstasy and other drugs.  He is on the verge of being broke.
My friends are highly concerned about my physical safety (and to a lesser extent that of my son) and worry that my ex will harm me given the level of venom and hatred toward me that they witnessed in him.  They are actually worried about the women he is in relationships with too because he expressed a level of hatred toward women in general that highly alarmed them.  These friends are level-headed and not typically given to histrionics.  They felt compelled to share this information with me.
Trouble is, I have no clue what to do with it.  My interactions with my ex are so brief these days that I can't really gauge his stability.  My son reports few concerns during his overnights with my ex (although he is a typical monosyllabic teen and doesn't tend to share much emotionally overall). My son has never been a trigger for my ex.
One of my biggest difficulties has been trying to navigate this situation with my in-laws.  They finally admit that my ex was acting a little strange last year but they want to believe that this is due to a mid-life crisis and put the whole ugly episode behind them.  Their denial is deep.
Here I am - trying to detach and thinking I'm actually making good progress - and now I feel like I'm being pulled back into the murky depths of BPD again.  Do I just ignore the concerns of my friends, or relate their concerns to my in-laws, and/or keep calm and just carry on?  (Just to clarify, there was one episode in my marriage over a decade ago, where my ex in a complete rage attempted to inflict lethal harm on me.  I never witnessed this level of abuse again even during his complete dysregulation last year but I know that his capacity to seriously harm someone is possibly lurking there during an out of control rage).
I can't see the forest for the trees here so all insights are welcomed.
Warmly,
B

[SlothMaiden]

Hi Baglady,

I'm glad to hear that you're safe for now and that he hasn't come to you yet. I am new to this detachment thing so I don't have anything to say much about how should you proceed. I understand you've had a rough year trying to let go. I just wanna remind you that every progress you have made so far is worthy and not a waste and don't let your ex's actions hinge you from your goal. I believe you've known by now that these behaviors are just how he is with BPD (or other mental illness). And if you keep up the boundaries and don't let him step on it, I think you'll be fine. Anyway, if you still feel doubt, we have your support here.