I think they are leaving it open so that she can come back if they need her too
Although, like someone else has mentioned, why would he ask Chelsea to go with him to identify her body if he knew it wasnt going to be her?!
Although, lol, saying that, I can't understand why the police havent been over to say that she didnt commit suicide, but was infact strangled...because a quick look at her body would reveal bruises around her neck, and a post mortem would reveal no water in her lungs
So, in light of that, it CANT be Denise...so she HAS to come back...
On another note...is it me, or is Denise/Dennis/Den the most unlucky name for Eastenders or what?! (dirty den died twice once in the canel, once in the Q.Vic, Dennis was shot in the square, and now Denise...)