Yes, I have a 'break'... either planned or unplanned about once a month. DS goes to my parents for the night. Either because DH and I have something planned (bday dinner, night out or something) or my parents offer that day.
Occasionally if we are having a particulary bad arvo and DH isnt home DS will go to my Dads (they literally live a min away) and spend 30-60mins whilst I get dinner ready, or clean up, or do nothing!
I may not win any mother of the year awards but I keep my sanity! and DS gets the best parent I can be from having that time away.