I don't think it was gentlemanly of him to go to the press. If it was an amicable split -- just leave it at that.
Good for Georgie to not follow his route.
I don't think dating Dec has played a huge part in her rise at Skysports and generally, her profile. She has a good personality and being on A League of Their Own with James Corden, Freddie Flintoff, Jamie Redknapp, and John Bishop has done a lot more for her than Dec.
Freddie Flintoff, whom she became good friends from ALOTO, gave her an exclusive interview when he announced his retirement from cricket. It was pretty good interview and probably, imho, helped score her interviews with Henry and Bolt.
So while dating Dec probably put her on people's radar, having strong sports connections with Corden, Flintoff and Redknapp helped open more doors of opportunities.