While it is taking forever, I think time is going slowing. After all, Hope married Aiden, almost died, reunited with Bo, went to a homecoming party, went to the park, had Bo die in her arms and returned to an empty house all in 2 days time.
Following that logic, Abigail and Ben have only been at the cabin the same 2 days (they left the night of the wedding) and she went into labor a day later.
Since no one else changed clothes, it going very slowly! But both stories are on same timeline.