They've won three trophies already this season (Community Shield, UEFA Super Cup and World Club Cup) are in the CL last 16 and are in the final of their FA Cup... and you call this a curse? Seriously mate... do your research. All teams lose hunger for the league title after winning it so many times... it happens. Real just also happen to be stronger this season in the league... head to head, Barca still destroys them. And Cesc is their second top goal scorer (guess who he is second to?)
I don't see how Cesc could have have hurt Barcelona, yes the formation thing was an issue because he had to play but that is sorted now. The league may have already gone but there is still the Champions league and the Copa Del Ray.