I think, whenever 4 couples meet at a house, that you would like all 4 to play each other once. Is that right? In which case the following is the basis for a solution with 11 sessions.
(9 6 11 3) (1 5 8 2) (4 12 10 7)
(11 12 3 2) (1 7 6 4) (9 8 10 5)
(11 9 4 8) (2 10 6 7) (3 12 5 1)
(1 11 7 10) (8 2 3 4) (6 5 12 9)
(10 4 5 3) (2 7 9 1) (6 8 12 11)
(8 3 6 1) (12 4 9 10) (7 11 5 2)
(7 3 9 11) (10 2 12 8) (5 1 4 6)
(2 6 10 3) (8 9 7 5) (11 4 1 12)
(3 5 7 12) (6 9 2 4) (10 1 11 8)
(5 10 11 6) (3 8 4 7) (12 2 1 9)
(9 3 1 10) (4 11 2 5) (12 7 8 6)
Each couple numbered 1 to 12 should meet every other couple exactly three times. Of course you still need to try to optimize the assignment of houses.
Does that help?