Well, what is best for everyone is not always "comfortable", and that can be hard. Sometimes a little space is good. Sometimes it is easy to get lost in a relationship and feel like you are losing YOURSELF. It's good to spend time with each other, and it's good to spend time with other people too (friends, etc, night out with the guys..)
Space is needed sometimes, and it's good to offer that, and not be smothering... but he also has to realize that your job is hard and you need a break too sometimes. You have other kids, it sounds like... I stay home with mine and it's more stressful than a "real" job (whatever that means!)~
Is there a way for him to take over with kids every now and then, and let you have an evening off? Go to a movie with a friend, go shopping, even just doing the groceries alone can be HUGE. You start feeling more at peace in yourself, and it reflects in the relationship too.
We try and have "us" nights every week where we spend time together, "family" nights where we hang out with the kids, and nights where hanging out with friends, away from home, etc, would be fine (or we have someone over). All 3 are nice, and all 3 are needed on occasion.
I know it's hard not to stress about it... but that may actually be part of the trouble. It is hard to really help without knowing details (not asking for them), but if you want to chat, you can feel free to PM me here and I'll offer what specific help I can. Hope you can sort things out, in any case.