If anyone's awake, I need some advice, perspective and hopefully some future encouragement.
Context: partner of 15 years has a history of periodic anxiety, depression and low moods which are usually fairly well managed with medication, plenty of 'me time' and general pandering. We have 2 DC, 8 and 11. We have recently agreed to separate but haven't been in in a hurry as things haven't been totally dire, but in recognition that it is hard work living together, mainly on account of his MH.
P lost his temper last night, escalated really rapidly over a small misunderstanding, and ended up shouting "Fuck you!" and slamming a door really forcefully into the room where youngest DC and I were sitting eating. DC have never seen anything like this; and were terrified. I'm not at all argumentative or shouty, and P is more likely to be moody and isolate if upset by something, which is still an uncomfortable feature of family life, but much less explosive.
P ended up erratically running around trying to apologise to DC, blaming me, attempting to make a phone call which I knew he would deeply regret, and when I unplugged the phone (it really was for the best before anyone suggests it might have been controlling), making veiled threats, all of which the children heard. He then went upstairs to their room and launched into an emotional 'explanation' of why he'd lost it and how we'd be going our separate ways as there was 'no room' for him in our family. He then retreated to his room for the night. I put DC to bed, acknowledging their feelings, but didn't add to the mess by further explaining. I didn't want to confront P as he seemed quite uncharacteristically unhinged, and I didn't want him to go off on one again, so I have stayed awake / dozed through the night trying to process wtf happened.
In a couple of hours the DC will wake up and wonder what on earth happened and how to be in this awful situation. I am furious with P for his outburst and so uncaringly dumping the separation bomb on our DC, which, as he also dropped in there, will entail selling the house they've lived in all their lives. They're in shock. I'm so angry on their behalf, but in the cold light of morning, I don't want to say or do something that will endanger their future relationship with their dad down the road; they're obviously upset now, but are likely to feel like they still want a relationship with him once things calm down. I'm so angry, I feel he's broken them. I want them to know their feelings are valid without overlaying my own anger and upset on top of theirs. How do I support them with navigating such big feelings of betrayal and loss (and likely fear) now?
I now want to proceed much more quickly with our plans to separate, like today or this week, but want to avoid unsettling the DC further as I've no actual plan yet, and nowhere to go immediately. There is no way P will be going anywhere until he absolutely has to. So how do we stay put and carry on functioning while fast-tracking separation, which, owing to organising house sale and limited finances is likely to drag on for months?
And as for P, perhaps I should be concerned about this turn in his mood and try to get him to seek some help, but all I see is the look on my youngest DC's face when he shouted at me and slammed the door at us, and I feel I'm past caring.
And please don't anyone suggest it was a storm in a tea cup or that it'll blow over; it really doesn't feel like that.
Sorry for the rant, I am trying to be pragmatic and think long term while also feeling incredibly angry.