"You" refers to Gil, not to yourself. I apologize for my unclear statement.
Before we get more information about Parker, please don't casually think that Parker is a hypocrite. He doesn't even have his episode. Please respect Parker.
Don't forget that Gil asked Parker to stop his sexual behavior, not Parker to take the initiative to destroy Gil and Lars feelings. How close Gil and Lars are is none of Parker's business.
According to Parker's habits, he can't use diet as a bargaining chip to trade with Gil. This may be Gil's wishful thinking, so Parker doesn't want Gil to manage his diet.
Gil asked Parker to stop his bad behavior, but Gil didn't do it and still did these bad behaviors to Parker. This is conclusive evidence. Can I also say that Gil is a hypocrite?
If Gil doesn't want to go back to Lars, is it necessary for him to let Parker stop his sexual behavior? Isn't this superfluous? You also said that Gil is an expert in sexual psychology. Parker doesn't like his behavior. Only Parker's think, Gil is not clear?
Parker just said that teacher-student love is a bad behavior, but he never interfered that Gil likes Walter and Lars, and anyone.
As for Parker calling Gil Gilbert, he said that when Gil no longer behaves like a child, he will stop doing so. Parker does have his own inner thoughts, including that he told a lot of lies to Walter, but this does not mean that he is a hypocrite. Please respect him.