The pair were spotted having an emotional chat at the bar of London's Mayfair Hotel on Monday, leaving onlookers to wonder whether they could be close to a reunion.
A source told The Mirror: "Feelings don't disappear overnight. Dougie would love for them to give things another try. They were perfect together after all.
"Both of them thought their romance was for keeps. They set up home together and Frankie really did believe Dougie was 'the one'."
Sandford split from McFly's Poynter last month and has since been left upset by false rumours linking her to Calum Best and Ashley Cole.
The insider added: "Frankie has been beside herself lately. Her fans abused her on Twitter for moving on from Dougie so fast when, in actual fact, she is still getting over their split. It was all getting too much, so Dougie rushed to her side to comfort her."