By Emma Wilson Christina Aguilera has devastated fans after abruptly cancelling her Las Vegas residency after just two shows. The 43-year-old pop icon announced in October that she had signed up to perform a 10-date residency at the Voltaire Belle de Nuit venue inside Venetian Resort and Casino, which would kick off on December 30. However, Christina was forced to postpone her string of gigs after just two dates, and told her heartbroken followers she was too ill to take to the stage. Taking to her Instagram Story, the Beautiful hitmaker wrote: “After welcoming you all to the new year from the…