Where It All Goes Down
Even though Shakespeare doesn't specify a physical setting for Sonnet 147, we can't help but imagine our speaker in a hospital room. After all, the guy kicks things off by comparing his sexual desire to a "fever" (1). Then he proceeds to describe his lust as a horrifying "disease" (2) that makes him so "ill" (3) that he's afraid it's going to lead to his "death" (8) because he can't get his "sickly" (4) sexual appetite under control.
Of course, we know this is an extended metaphor to describe what's going on in our speaker's mind, which points us to the sonnet's psychological setting. Comparing his desire to a fever gives him a chance to describe what it feels like to be crazy in lust. At one point, he even says he's been talking and acting like a madman (11). He says his desire has made him "frantic mad" and has caused him to completely lose his ability to reason (10).
That's probably why so many theatrical performances of Sonnet 147 imagine the speaker as a patient in a psychiatric facility.
Heck, we've even seen the sonnet performed by a bunch of actors dancing around in straightjackets.