According to The Mirror, the I'm A Celebrity star contacted Winehouse after Fielder-Civil spoke out about their relationship in a Sunday newspaper interview at the weekend.
The troubled singer was granted a 'quickie' divorce from Fielder-Civil last month after returning to her new home in Barnet, London following an extended break in St Lucia.
A source explained: "David moved into the area a while ago and was introduced to Amy through their mutual mate Matt Willis. Then he kept bumping into Amy and they kept in touch.
"When he heard she was back from St Lucia and Blake had been spouting off about her again he invited her on a night out so that she wouldn't stay at home alone feeling depressed."
The insider added: "A few drinks did nothing to cheer her and she ended up sobbing her eyes out in the pub. She was inconsolable."
However, Winehouse was said to be feeling "a lot more positive" when Gest invited her to his house for a second meeting on Tuesday.
A friend of the star said: "David has been a support to Amy through a low point."