I can't take birth control, this being a huge reason.
Go get a new lingerie you feel great in. Also, maybe you two can do a fun workout together, like on the kinect for the wii or dance revolution or some fun workout dvd, or go for a brisk walk pushing a stroller or something like that. It not only increases sex drive, but makes you closer like a little date night a few times a week, plus it helps your body get in shape. Strive for a date night once a week... even if it means cuddling and playing a fun board game or watching a movie or reading a novel together when the kids are in bed.
Anything is better than sitting on the couch. Ya'll just need to get motivated.
Also, when I start to complain about my after baby body, my husband says, "You had an 8 lb baby in there, what did you think would happen!?! Your body is amazing for what it has been through!" You remember that applies to you as well.