very short background: My mother was the unwanted final child of a very difficult (violent) relationship. She was beaten and told she was unwanted a lot as a child. She is a positive, energetic adult who threw her whole life into her family and has brought me and my sister up to be very close, with good futures.
My dad is calm, patient, restrained, but rather emotionally detached.
They are both in their mid-60's.
From time to time mum has "episodes" where her and dad will have a huuuuge row and she will go off for a walk/drive/whatever to calm down. The argument is then forgotten until the next one. The last time this happened was about 7/8 months ago.
And then today....This morning she phoned asking to see us later, we arranged we'd catch up this afternoon as we had friends around this morning. my husband, dd and I went out for lunch and when we got to our destination, we had a call from mum who was crying, explaining she'd had a pointless row with dad and she wants to see us. We said we'd finish lunch then come home, but she could stay at our house until then. She asked me not to tell dad she was there and I agreed not to ring him.
Instead I called my sister who is in the area visiting friends, she went to make sue mum was ok. Mum hit the roof saying no-one was to know where she was, and now she'd have to leave
- she got in her car and went. We returned to an empty house.
According to my sister, mum was in a complete state, crying and aying she will leave dad, she can't live like this 
Mum is prone to over-emotional outbursts, she often fees like the world is ganging up on her, she cannot take anyone disagreeing with her, she will not say sorry.
Dad is sat in his house drinking coffee. I have not spoken to him.
I am pretending all of this has not happened (I panic a bit in such overly emotional situations, - I am not particularly emotionally intelligent) - what should I do? I feel wretched, like mum wanted to see me and that I should try and sort this out, but it's not that easy is it
I have no idea what I want anyone else to say or do really, I think I just needed to get this off my chest :)