It's only weird to you because you are almost certainly straight, cis and male. Let me explain.
All of society is structured around your identity. Like the fish, you can't even see the water because you have always been in it. I'm unlikely to help you see the water, but let me at least try.
If you meet a friend, he might comment he saw a movie with his new girlfriend. He shows you a photo on his phone and you say she's really cute and nice catch. He asks if you want to grab a beer later. You say you have to pick up your wife from the airport later and pick up the kids from their school.
All of this, the girlfriend, the comment she's cute, the wife the kids, they are your life. It is who you are. If someone asks what you are doing later, it's all you have to say, because that's what you do. It is your identity.
I have a partner. We have lived together for 14 years. In order to tell you anything about myself, I have to tell you about him too. It is my life. It is what I do. This is who I am.
Coming out is something you do with each and every new person you meet. I am not rubbing your face in my sexuality. I'm just talking about me. If I tell you I went out for lunch, but avoid telling you with who, that is in the closet. If I tell you it was with my boyfriend, that is out of the closet.
So yup, done hiding here, and not going to start again because some people might be clueless or treat me as less.
Edit: nice, downvotes. Did I make you feel silly for listening to taking points from bigots?