Point them out
Call it as you see it. Don’t go along with the conversation as if nothing is bothering you. However, you need to point out that the other person is being aggressive with an empathetic statement rather than agitating them even more. Avoid using the words ’you’ or ’your,’ and try something along the lines of:
’There is no need to stress, we will resolve it/find a way/work it out.’
’Could you please lower your voice.’
’I’m sorry, can I say something I believe is important/might help?’
’I understand this can be stressful/upsetting.’
If you do this early on, it will help knock them out of the place of being unaware of themselves and be more conscious of what they are doing. As a result, it can help the person be more open to hearing whatever you say.