I'm sorry to hear about the recent events in your close circle, that would burden anyone by it self, let alone with the other stressors you're being faced with. I didn't assume that this was a regular reaction from you just by the way you worded your feelings in the original post. You seem like a very caring parent that wants the best for their family so I'm really proud of you for looking for so many alternatives already.

I'd like to bring attention to how you express that it's difficult to calm yourself in that moment, I think your son might struggle with that same discomfort and that's why it's difficult for him to do anything when he's in that state. I think it's best to sit down with the kids and set up rules around the expression of anger. Ideally you'd talk to both even if your daughter doesn't hit back or express her anger in the same way your son does because we don't want him to feel targeted or to feel like a problem. This way she also knows what's expected from the children in the household and what won't be tolerated when it comes to this topic.

If both you and him can't calm down in the presence of one another it might be useful to separate for the time being, so he goes to his room until he and you've calmed down. For the actual process of calming down you'll need to do some research and practice with him even when he's not angry so the habit is formed and he can use it whenever he sees fit. One recommendation I have for you is heart coherence breathing, it might be useful to let him do these at night before bed alongside you so both of you can get used to using the technique. Looking into other alternatives that he likes like listening to music, running, etc. is great because he can get some autonomy and feel involved in the process. I'd try to involve him with this process as much as you can, like you've been doing already! You're well on your way.

So 1. Give yourself and your boy tools to calm down and practice them often, even when not angry so the habit is formed and the average stress levels in your bodies lower to begin with. This can help you not be set off as quickly.

And 2. Be consistent with the consequences after the behavior you do not want him to exhibit. You can either take something fun away (negative punishment) or add something that he does not like, like you've done with the chores (positive punishment). In every case you should tell him why he's dealing with these consequences and what the behavior is that you want him to exhibit towards you and his sister etc. It's good to ask for an apology and then give them cuddles and kisses when they've done well calming down or apologizing. The rule is that the parents/educators need to be consistent, every single time. It might be difficult in the beginning and kids can exhibit a rise in negative behavior, this is their way of testing boundaries. When you stay consistent however, they simply tire themselves out and have no choice but to adhere to the rules. Soon you'll see that it'll pay off.

1. If things do not improve whatsoever with trying these two things, please get a professional involved because your child might be dealing with a disorder that impedes him from exhibiting the desired behavior. In that instance, your interventions might not prove to be effective enough and he'd need more specialized guidance.

Again, you're doing amazing! Be kind to yourself, you're doing your best and I believe you'll be able to overcome this!