I know many of you have wondered where I've been for the last couple of months. I'm sorry if I've worried anyone. I guess an explanation of sorts is deserved.

Towards the end of last year I was suffering from burn-out, compounded hugely by my old enemy SAD. My fibro was playing up too, and it was all a bit too much. So I decided to take a short break from Twitter and politics to give myself a chance to recharge some spoons. It was my intention to be back after a couple of weeks, so I didn't feel it was necessary to announce my departure.

Of course, life doesn't always respect our plans. Firstly, my flare-up was rude enough to continue for ages. But that was just an annoyance compared to the blow our family was about to suffer.

Just before Christmas, I got an unexpected phone call from my dad. He never phones; that's my mum's thing. The tone of his voice instantly told me that something was very wrong. He said he needed to talk to me and that he'd come over later on. If phoning was unusual, a visit is just downright weird. I spent the next three hours overdoing it, doing housework I'm not fit to do, completely thrown by something so out of the ordinary.

A thought has haunted me for some time. A revelation I had about chronic illness. “If I ever get cancer, I probably won't even notice it until it's quite advanced.” I've even said those words out loud. Cassandra syndrome never fails. Turns out I was right, but it wasn't about me.

My dad had come to talk about my mum. They'd found a large tumour in her bowel. A long history of colorectal problems, labelled somewhat dismissively as IBS, meant that it had stayed under the radar for far too long. Consequently, we were now facing a medical emergency. Although at this point the “C word” was not a confirmed diagnosis, the presence of further abnormalities on the liver did not bode well.

As you can imagine, I felt like my heart had been ripped out and thrown into a blender before my very eyes. My mum may be a grandma, but she's a young one. She looks after herself. She doesn't smoke or drink alcohol. In fact, it would be hard to think of somebody in a lower risk group. If ever there was proof that cancer doesn't discriminate, this is it.

And the rollercoaster had just set off. A matter of days later my mum was unexpectedly admitted to hospital, having collapsed while at an appointment. Thank God for the NHS and for the skilled surgeons they employ. Because of them, mum is still with us. She is, however, very sick. The tumour in her gut was indeed malignant, and her liver is covered with cancer. As I write, she's back in hospital, with what looks like pneumonia.

Mum's a fighter, and the doctors are determined to do everything they can. We don't yet know how this story is going to end. What is certain is that it's taking its toll from all of us. The rest of life still goes on, and I have two very special children who present their own challenges. In order to have the emotional strength to support my family through this difficult time, something has to give.

And so, with some reluctance, I have had to withdraw from the battles I had been fighting, and concentrate on those things closest to home. For a while I must depend on others to keep working to make the world a better place. I'll be back on Twitter in due course, when I trust myself not to get drawn into things that I don't have the energy for. For now, my spoons belong to my family. I hope you understand.