Hello WarriorMom and welcome to the family. I am so sorry you're going through this and it does sound like there's quite a few BPD traits present. We aren't here to diagnose but it does help with giving practical advice on how to deal with this mess.
A few questions-
Were you already separated or living at different places? I noticed at one point you said he showed up at "your home". I just want to make sure we're all on the same page about your living arrangements during the relationship.
My question is , is this a discard or is he likely still splitting. He's since added me back on whatsapp but ive heard nothing from him for nearly 2 weeks now.
Splitting usually happens quickly- from a few hours to a few days. It's possible for it to last a few weeks, but that's more rare. So this was a discard...but it sounds like it happened when he was splitting and clearly dysregulated.
Why does that matter? Because he probably wants to reach out but is too ashamed to do so. You shared that his story kept changing...that's because he was unstable and the facts were literally changing in his mind over the course of those conversations (AKA splitting). Plain and simple, you hurt his pride when he was in a vulnerable state and he ran.
Please understand though that I'm not blaming you- none of this is your fault. The problem here is mental illness and disordered thinking.
I'm just at a loss to know what to do. I do love him but just feel its hopeless now, he said some really awful things I feel I just cant get over but I dont know how to move on with my life or stay and try and encourage him gently to get help if he comes back.
I know that feeling all to well and it's so tough; do you reach out and inevitably face more abusive accusations, or do you walk away? You posted in the "detaching" section so the advice you receive here will be geared towards walking away...is that what you want?
It's okay if you're undecided at this point and we can certainly move it to the "Conflicted" boards so you'll hear opinions on both sides of the fence.
About the awful things he said- that's terrible. But it might help to know that he said these things in one of the worst moments of his life as his world was imploding all around him. Maybe that sounds dramatic, but that's what it feels like for someone with BPD to experience rejection and second guess their relationship. Their inner pain makes them choose the "nuclear option" to blow it all up and ensure there's no coming back.
Finally, what to do. This is the biggest thing at the moment because it's the only thing you're fully in control of. Focus on your own mental health and wellbeing. You've been through so much lately and you need a chance to heal...and the healing starts by processing this mentally. Until you come to grips with what happened and why it happened, it's like you're stuck with nowhere to turn.
So let us help you with that, talk it out and tell us where you're struggling.
One more thing- the part about gently coaxing him back so you can encourage him to get help. That sounds like the sensible thing, but people with mental illness don't like being told that they need to get help. You may have the best possible intentions, yet what you say and what he hears will likely be two very different things.
You can't go back with hopes of saving him- he must save himself by choosing to get help. nobody in this world can convince him to take therapy seriously and actually make long-term changes. That has to come from within or it's worthless.
I hope that helps and again, I'm so sorry you're going through this.