Alison never led a particularly happy life, weighed down by both her and her parents' guilt over the death of her younger sister Cheryl when Alison was still a child herself.
After Kevin Webster brought her back to Weatherfield over Christmas 1999, it seemed like a new start - she was pregnant and they married. However, the later stages of pregnancy and birth of Jake Webster was complicated, she passed a Group B Streptococcus infection onto him and he died the same day.
The burden of Alison's guilt proved too much, she cracked and walked out of the hospital with newly-born Bethany Platt. Kevin finally found her, but in the depth of her despair, she ran into the path of a lorry after handing Bethany to Kevin.
First and last lines
"I'm alright, thanks." (First line, to Janice Battersby who asked her if she wanted a cup of tea)
"Don't wake her, she's comfy as she is. They'll see I looked after her." (Final line, just before throwing herself in front of a lorry)