Just finishing the 5th season of Dexter and partway through the season Deb ends up going to live with Quinn because of their relationship and because of Dexter's old apartment becoming too crowded for her with the baby and Dexter being there all the time.
After Quinn's betrayal is revealed, it is was never clear about where Deb continued to live. It was obvious she did not stay with Dexter as Lumen moved into the apartment after Jordan Chase started to get close. But it is never shown her being at Quinn's apartment after their fight in the interrogation room about Quinn suspecting Dexter as Kyle Butler.
Any ideas where she could have been staying? I find it very odd that she would not return to the apartment after being confused Quinn's loyalties.