First the obvious one-- do you believe that one can relieve stress from sexual pressure by committing a sexual act? I think it would have absolutely the opposite effect. If one is having sexual pressure, the worst thing for the person to do is to do anything sexual.
How does that track? Why would sexual stress be exacerbated by committing a sexual act? Of course, that is, unless you feel guilty about committing sexual acts, a trait which seems almost exclusively limited to people from your camp.
And, there's a simple non-psychological answer: positive endorphins and pleasure. Obviously, there is a biological drive to have sex, and satisfying a biological desire without causing anyone else (or yourself, I'd argue) harm has positive consequences.