Hello KSCO229
I would like to join
Merlot in welcoming you here.
Well, I can certainly relate to what you have written having experienced the same communication problems with my uBPD son. A slight difference, my son was always in denial and thought that I was the one with the problem. I know now that the only problem I had was that I didn’t know how to communicate with him effectively, and it is only since just before he went NC (no contact) with me that I found this site.
So, your son is diagnosed and it sounds like he has accepted that which is great, and you want to support your son, which is also great.
There are TOOLS which can be found on the right

as
Merlot has already pointed out. A good starting point is Listen with Empathy and Validate the Valid.
I can also recommend a book Loving Someone with Borderline Personality Disorder by Shari Manning, an excellent read.
You say that you would like to find a therapist for yourself, you are very wise to recognise that you will probably need help and support. I would recommend finding a therapist who has a good working knowledge of BPD and who is able to help you understand and communicate with your son x