At the time, i took the above outburst as a pure expression of distress. Now I am not so sure. Invoking self harm to demand or elicit a reaction from a partner is a pretty terrible thing, and the fact in the weeks after I was snappy, stressed or just wanted to hide and fall asleep when i saw uBPDx, and that this was characterised as me being 'horrible', is also awful.
The fact a close friend had previously lost a close person in very proximate circumstances to suicide, that i told uBPDx this affected me a lot, and yet he had no qualms continuing to bombard me with self harming rhetoric to secure a desired response or experience his own emotional release, is also pretty selfish.
When a mentally ill person "threatens" self-harm, take it seriously. That means picking up the phone, calling emergency services, and tell them that your partner is threatening that. The police will come, an ambulance will come, and he will be taken for a psychological evaluation. He will say or do anything to get out of it, but you repeat what he told you to whoever shows up.
A few things will happen once you do this.
1) He will be furious at you for "betraying" him. Yet, you're doing exactly what we're taught to do as kids, in an emergency, you dial 9-1-1 and tell the truth. Explain that you did the only thing you could do to help him in that moment when he wouldn't talk things out and deal with his emotions.
2) He will no longer play the "I'm suicidal" card in arguments unless he realizes that he actually needs immediate help. One trip in the back of an ambulance with an involuntary hold is usually enough to get the point across. That's not something to be "weaponized" unless you actually want to receive the help you're claiming to need.
3) The hospital systems in the US are virtually useless for these types of things and it frustrates them as much as it frustrates you. He will be held until a psychiatrist can interview him, and if he's deemed a threat to himself or others he will face a mandatory hold (usually 3-7 days). They will try to help him with anxiety and other symptoms, but real change is up to him.
Side note- while he may be saying stuff like that to upset you, deep down a part of him means it as well. He's hurting mentally and has no idea how to express what he needs in the moment. What he actually wants though is compassion and forgiveness for the way he's acting, even though he is incapable of expressing that.
It's honestly sad and I feel bad for your husband...but that doesn't give a free license to abuse you either. There has to be a balance in there somewhere.