Let's be honest, do you think he was gay?

No.

Bateman may have hated women, obviously succumbing to his frequent, uncontrollable urge to dismember them. But he seemed to rather enjoy fucking them as well.

On the other hand, Patrick also brutally murdered several men throughout the film, though I don't recall any indication of sexual attraction towards any of his male victims.

Bateman was a just a narcissistic sociopath—I'm not sure what leads you to believe he was also homosexual.

He's definitely not gay since we've seen him have sex with women and enjoying it, before killing them that is.

As for his male victims, one of them was gay and thought Bateman was flirting with him or something when trying to kill him in the bathroom, and Bateman got disgusted and left, couldn't even bother to kill him.

no he was a crazy homophobic slut

The opposite of gay. He was normal.

You do remember Louis tried to come on to him and he walked away in disgust.

Everything considered? Like what? There is absolutely nothing in the movie to suggest he was gay.

The book is about the author's experience with fame in Hollywood.

He admitted he was homosexual eventually....so your conclusion is probably correct.