Hi lindaz141,
I'd like to welcome you to the community, I'm glad that you decided to join us.
Is there any wisdom as to how to move past this anguish and look at him as a different person, and not the person I thought he would be?
As I was reading your post, radical acceptance comes to mind. When we wish for things to be one
Radical acceptance comes to mind. When we wish things to be different, an event, a loved one etc... .when they're not, it causes anguish. Your son suffers from social impairments, you described BPD well, a pwBPD ( person with BPD ) are emotionally arrested at the young age of a child, it's like a child in adults body, they can't regulate their emotions or self sooth.
I'd suggest to read as much as you can about BPD, the behaviors don't make sense but there is fundamental logic to the behavior, it helps with normalizing BPD and depersonalizing the behaviors, it's not personal it's something that your son is going through, although I know how difficult the behaviors can be. Another way to process the grief is by talking about it, tell your story, share with others so you don't feel like you're going through this alone, it's easier when you grieve with others than by yourself. That said.
If you think about something that causes you a lot of pain, it could be an event that happened in the past, a loved open, it can be difficult to accept pain in our lives and often we wish things were different, why did I go through a painful event? Why won't a family member stop behaviors that are hurtful to others and to me, it's accepting that pain, instead of trying to reject it subconsciously, we make a conscious effort to accept that we had a painful event happen in our lives and in the case of your son, accept him wholly, all of it, he is who is, he has social impairments, a disorder where he can't regulate his emotions and lacks impulse control.
Radical Acceptance For Family Members (DBT skill)I hope that helps.