Every word is made up, that's how we have language.
Also, to me, homophobia is not agreeing with being lgbtq+ AND being mean about it, not just not agreeing with it, people have their own beliefs, but it's when they are mean about it.
We don't treat them like they are mentally ill, we are just saying that they don't think being lgbtq+ is right and is mean about it. I mean a lot of them treat us like we are mentally ill already.
My best friend has another friend who doesn't think being lgbtq+ is right, but she's not a homophobe, she's perfectly fine with my best friend being bisexual, and is never mean about it, she just doesn't think it's right. That person is not a homophobe, she just doesn't think it's right. If she was mean about it, then yes she would be a homophobe.
Okay don't use the t slur, it should only be used by trans women.
Pffffft that's just dumb how you said that
1. It's not a mental illness, if you want to call it a mental illness, that means gender is a mental illness lol, plus you were just saying how we treat homophobes like they are mentally ill, yet you say it should be a mental illness
2. It's not a lifestyle, it's just living as your gender. This is the definition of lifestyle:
"the way in which a person or group lives."
Being transgender is not a way we live, it's what we are.