Disclaimer: They don't belong to me, but I borrow them to make them dance.
It wasn't him.
House had no problem with prostitution. The jokes were exaggerated, but he'd paid his way through a few lonely nights. He didn't even have a problem with the inherent fakeness of it all. He knew what was going on, and as long as he understood it, he could accept it as a natural part of human behavior. So really, he should have been perfectly fine.
But as he sat there with a man he was paying to be there, laughing and wishing so desperately to believe the lie, he couldn't stop the little voice in his head. The one that told him to stop pretending – that the man next to him wasn't the person he wanted him to be. That it might never be again. He was painfully aware of the self-deception. Of the indulgence.
So he accepted that it wasn't Wilson. That Wilson hated him, was done with him and would probably never come back. He accepted that he didn't care about this stranger, and this stranger only really cared about his paycheck.
And he indulged.