By Ellie McDonald & George Mathias & Rom Preston-Ellis A couple say their new build home dream has turned into a “nightmare” with it plagued by problems – including an infestation of beetles. Diane Jackson, 61, and partner Mark, 59, bought the £320k four-bed near Darwen, Lancashire, after selling their old property to their daughter. They were looking forward to the next stage of their lives – but have faced nothing but issues instead, they claim. The pair say they have discovered damp and mould alongside the insects and, as it stands, the home is unliveable. This has meant they’ve had to move…