Can't sleep without sex

Most nights, I'm awake until 3-4 am
Unless I get some sexy time with my fiancé. Then I'm out. I don't think it's because of the physical exertion. I'm pretty sure it's because of anxiety. 
I have always had really bad anxiety and sex helps me relax enough to fall asleep. 
But we don't have sex every night. Mostly because of his work schedule. 
Am I the only one? Does anyone have any advice for other, more attainable stress-reducers?