Because its OK for blokes to play away... apparently.. while Imogen got all the flack, Giggs (Even though he is a legend) got away relatively scott free.
Another example is Kristen Stewart, look at all the flack she got for having an affair, while the bloke she had the affair with was barely mentioned.
To be fair though, Kristen still has a career and I'm not sure Rupert really does now.
And Giggs did get some flack, though a bit less than he deserved, especially as he was also shagging his brother's wife. You can't go much lower than that.
Anyway, congratulations and best wishes to Imogen and her daughter.