Like others have said, it really varies on our work & stress levels and state of mind. We've been together 3 years, no kids.
We are affectionate and intimate daily--even if it's just cuddling on the couch at night or before we get up in the morning and a kiss before and after work. Up until a certain puppy moved in, we would have sex at
least every other day with every day being the norm. Then we had many rough weeks with monster puppy (reason #3000 to crate a puppy) and now the dogs have a gotten in the habit of sleeping between us (reason #3001 to crate a puppy).
Actually, last week we decided to end the dog cuddling in the morning--DH and Crossbone have a love fest every morning instead of initiating cuddling/contact with me--and enforce dogs sleeping on the foot of the bed. The dogs are confused, but it seems to be working
I'm not really a sex-every-day type person but I am not totally happy with once a week or less.