Isn't he gay?

So the other day I was reading a book by a couple of my favorite YouTubers ( Dan and Phil). Shortly after I had started reading one of my friend comes into the room. After he sees what I'm reading he says "Aren't they gay?" Which I respond with "No they aren't, why would you think that?" To which he responds "They look/ act gay." So with out knowing anything about these guys he thinks there gay which isn't right. They are just really good friend. That share a flat (which is an apartment for people who don't understand British speak) and tons of guys who are friend live together because it saves money. Your not gay just because you live with someone of the same gender. Just like being best friends with someone of the same gender doesn't make you gay. After I told him this he then says "Well isn't that guy that wrote The Fault In Our Stars gay" To which I response "No, John Green is not gay he has a beautiful wife and two adorable children." When I then ask him why he would even think that he said it was because he wrote a book from a girl prospective.  How shallow is that, a writer put him self up to a challenge. J K Rowling wrote the Harry Potter books from Harry's point of view. Did people think she's gay? Nope, but obviously if you are a guy and have a best friend or write a book from a girls prospective you must be gay. Also just because you act a certain way doesn't make you gay and just because you don't act a certain way you aren't gay. I watch an amazing YouTuber named Connor Franta and I had been watching him for about a year before I found out he was gay and never in my wildest dream would I have thought he was gay because he didn't "act" gay. So why do people think that someone is gay even if they're not? Also why is gay an insult because in my opinion we are all people and it doesn't really matter if you like boys or girls. What matters is that you treat everyone with love and respect no matter what. I also would like to acknowledge that the topic of gay people can offend some people but you are the person that decided to read this.

-Liz