Honeymoon together at least twice a year. The happiest memory of my childhood was when I was 6 years old and my parents went away to Israel together to try to save their marriage. Sure I missed my mother and father. But I realized that they went away for the sake of our family, even if, in the end, they wound up more distant than the Arabs and the Israelis.
Make arrangements for your children to stay with relatives or close friends, then go on vacation and act like newlyweds. Make love, giggle, and have meaningful conversations so you can rediscover that you're not just a mother of someone with a runny nose, but a woman with a beating heart. If this is something you can't afford, then try getting the kids out of the house. You can perhaps send them to their grandparents so that you and your spouse have time together at home.
Start dating again. Set aside a regular night for couple time. It's okay to meet friends, but save at least the first hour or so for just the two of you. Don't blow the evening on a movie. Get emotionally naked. Discuss your fears, and comfort each other in a way that allows you to really connect. Do everything you can to bring new surprises into your relationship, whether that means sexy lingerie or scented candles to heighten the mood.