His response was " I don't care what was on you FB , I'm dealing with so much right now , I don't want to hear about that" He was holding it together . . . So believe it or not, my son 'just' called. He said he wanted to say Hi and see how I'm doing. I told him and asked how he was doing. He went from calm to amped up. Saying- I am under so much pressure- I never want to talk about how I'm doing. Don't ask me. I called for a break.... I said OK, I won't ask and I started to tell him things in my life - what I was doing ... other trivia. He was calm and responded, asked questions.... Told me he loved me and to have a good evening. I guess I got my answer to stay at the surface
Great job! While I get the sense you'd want to have "normal," two-sided conversations with your son, it seems to me he is being fairly direct by saying, "I can't handle talking about my life because I'm feeling overwhelmed, and I don't want to hear about any of your problems right now, because that will stress me out even more, and I'm liable to explode." Basically he's asking you to avoid any triggering topics when he's feeling overwhelmed. That to me seems like some emotional control, because he resisted the temptation to lash out or dredge up some unrelated grievance and make you his punching bag, and yet, he stayed in the conversation. Would you agree? Even better, it seems to me that he recognized that he was a bit rude to you, and he tried to make it up to you by calling you back and wishing you a good evening!
Now, I understand that this might feel less than optimal for you, because YOU desire some closeness and communication, and you don't want to be constantly walking on eggshells, worrying that if you ask your son something as simple as, "How are you?", that he'll go down a negative conversation spiral. Trust me, I've been exactly where you are right now with the pwBPD in my life, thinking that if a "How are you?" is triggering, it's extremely difficult to have a conversation at all. There were many times I'd say something like, "You look nice, how was your day?", and all I got was a glare from my pwBPD as she escaped to her bedroom. My interpretation? She felt like a question about her day was an inquisition, tinged with thinly veiled harsh judgment, because she knew she wasn't doing what she was supposed to be doing during her day. Her coping technique was avoidance--escaping the conversation to her room. This was probably better than self-destructing into an angry, petulant mess. And in all the years I've lived with her (more than a decade), she's asked me about my life only once or twice. In fact, I think that's a hint for some of her issues relating to other people: she shows practically zero interest in anyone else, because all her mental bandwidth is occupied with thinking about herself and her ongoing "traumas". When I witness her converse with other people, the conversations seem to fizzle out quickly, because she answers questions with one-word answers, and she doesn't throw the "conversation ball" back. And then she wonders why she can't seem to connect with other people. Trust me, I've tried to engage with her, and it's like pulling teeth. The only "safe" topic is basically TV, and that's a tough one because I don't really watch much TV and don't have the same streaming services she has.
I guess that's why the general advice here would be to keep things light and superficial, and let your son take the conversation lead. Also, remember that this is probably temporary. If your son is feeling overwhelmed right now but actually holds things together and pushes through, he might eventually discover he can handle more than he thought he could, and he'd bolster his confidence and identity as a competent, independent dad/son. Then a greater percentage of conversations might feel "normal."