I agree with the above suggestions. I have been with my partner for what will be 5 years next month. I don't have children of my own as I'm unable to now, but we lost 2 and we take care of my nephews and neice so I can kind of relate. I know it can be very tough to even have a minute without the kids and when you do it seems you're constantly working. We've done pretty good keeping things very alive, but we've had moments like when I was ill.
I would suggest (when the kids are not with yall!) take a small road trip, I say small since gas prices are through the roof, but even just a trip to the store or an event you both will be attending and make the car ride play time! It can be loads of fun. I wouldn't suggest trying to make love while driving, but other play things are extremely hot! You could always take a small trip to somewhere quiet where y'all would be alone. Where we live (on a mtn.) there's a huge water fall and pond area in a wooded space. It's pretty popular and there,but not many people until the summer time. If you have any types of places like this in your area, they can be very fun too! It's good for getting away from the craziness of everyday; phones ringing, work, house work, kids, etc.
I wish I had better suggestions, but I can't think of many. Most people would say a candle lit dinner, but I'm not that type. Sometimes we have fun shopping together! If your man's interested, it can be a fun experience.
One of our favorite things to do is our family get-togethers, but that isn't exactly alone time. It's really nice to have a quiet evening with family/friends/loved ones and your partner to just sit on the porch, eat,sometimes have a drink or 5 and talk! Maybe I'm too much of a country girl, but it really is a fun, relaxing idea (if you get along with family members)