I know how awful it is to lose a child - my baby died 12 years ago, and it was the most painful thing I've ever experienced.

And when you bear in mind that I'd once been in a road crash that crushed my skull and broke most of the bones in my body, I do know what pain is.

Nevertheless, I still can't even begin to imagine the pain Anne-Marie Cockburn must be going through as she deals with life without her only daughter.

Anne-Marie is a single mother from Oxford, and her daughter was 15-year-old Martha Fernback, whose death last July hit the headlines because it was thought to be linked to her taking an ecstasy-type pill.

What exactly she took, and how she got it, is still under investigation, but in the meantime her mother has been trying to deal with life after Martha.

Amazingly, she's coped by writing a brutally frank diary about her grief, which has now been published under the title 5,742 Days - the number of days Martha was alive.

As I said, I know the pain of grieving for a child. But while my pain was bad enough, I can't even compare it to what Anne-Marie's experiencing. While both our hopes and dreams died with our children, I had only known my baby boy for nearly two days, while Martha had been part of Anne-Marie's life for 15 years.

I'm not saying it's easy, and you need support to find the strength to do it. While I got that support from my husband, Anne-Marie got it from her writing."

I wasn't used to having my baby there all the time, but Anne-Marie was great friends with her daughter and just the two of them lived together in a cosy little flat in Oxford.

And, crucially, I had my husband to cry with after our first child died. Anne-Marie lives alone, and while she has close family and friends, she's single and was unable to share her grief with a partner.

As she said to me when I interviewed her this week, she has no shoulder to cry on when she wakes up in the middle of the night.

But this woman is strong - probably because she is a single parent, not in spite of it. She's determined not to let her pain destroy her, and I know where she's coming from. While you have to grieve, you also have to move on and not dwell on the past.

I'm not saying it's easy, and you need support to find the strength to do it. While I got that support from my husband, Anne-Marie got it from her writing.

Despite being a writer myself, that's not something I particularly understand. I love to write, but I don't get any comfort from it. I've written about my son's death several times before, and to be honest it made me want to cry, rather than giving me strength.

I still can't even begin to imagine the pain Anne-Marie Cockburn must be going through as she deals with life without her only daughter."

But then I didn't need it to give me strength, because I got that from my husband. Anne-Marie's not in that position, but thank God she found a way of coping with her tragedy despite being alone.

I moved on and had two more sons, but Anne-Marie's 43 and doesn't think she'll have any more children. But instead of wallowing in self-pity, as it would be so easy to do, she's determined to get on with her life and has very quickly produced a moving, eloquent piece of writing drawn from the depths of her despair.

It was either something like that, she says, or become a "mad cat woman" instead.

I thought what happened to me was bad, but there's always someone worse off. Can you imagine losing your only child at the age of 15?

Try to imagine it and then, if you're a parent yourself, be grateful for what you have. However badly behaved your kids are, at least you're lucky enough to still have them.

Lisa Salmon is a journalist at the Press Association.

This article is the opinion of Lisa Salmon and not necessarily that of BT.