And it all goes back to how they were raised, and how they internalized the messages from their family and their churches about homosexuality. I don't know this guy, but I know people like him. In some ways I can see a little of myself in him.
One of two things have happened here from what I know of this guy.
#1 - He was a rebellious teenager and was being extra gay because he was trying to get a rise out of his parents, but then he matured a little bit, realized how much him being gay was hurting his parents feelings, or their perceived reputation around town, and he decided that for his family he would pretend not to be gay anymore. This would give him better access to the love of his family that he craves. In order to prove that he's truly not gay anymore, he must, I repeat must, be extra straight. In Deer Park that means he needs to drive a truck and wear a cowboy hat and be a good republican and go to church. And in Deer Park if you are going to church it means that you are probably getting to hear about how terrible homos are on the regular. So he just gets inundated over and over with this message about how broken he is, which causes him to act out even more to prove how he's straight and therefore not broken, and it's a cycle that just never ends. In this scenario he's likely fucking his wife just often enough not to arouse suspicion, but his browser history is full of gay porn.
#2 - He was happy being gay but his family threatened to cut him off from their will, and so he's overcompensating to prove just how straight he is now so that he can stay in the will. In this scenario he will drop all of this as soon as the money from the estate is deposited in his account. In this one he's finding excuses to leave the state and he's fucking every piece of strange he can whenever he's not home. Also, his browser history is full of gay porn.
I could be wrong, but I suspect that he's sitting in one of those two scenarios. Had I made a couple of choices a little differently, I could absolutely have been #1 myself. I'm so fucking glad I picked correctly, because It seems like a really really miserable existence.