Avril Lavigne & Chad Kroeger: Consciously Recoupled?

Avril Lavigne and Chad Kroeger have separated ... but it didn't look that way Thursday night.

The estranged couple left the Sunset Marquis together in WeHo, 3 months after announcing their separation.

There are a few scenarios ... obviously they could have had a change of heart, or they took a page out of the Gwyneth Paltrow and Chris Martin handbook.