Yes I have always been out at every job since I was 14 years old, even though I have worked in some awfully homophobic and sexist environments. It can be very tiring answering the questions of the sheltered and confused, and I admit in recent years my tolerance for educating folks has waxed and waned. Recently I am just as likely to say "Google it" as provide a diplomatic answer. After 30 years I'm tired of being a 24/7 diplomat for the gay community.
My physical appearance does not allow me the option to pass as heterosexual since I am read as "butch dyke". Heterosexuals I've known who "read" as gay are quick to mention their opposite sex partners in casual conversation so I guess if I wanted to create a fictional life I could try it. That might be fun!
I know someone who invented a fictional baby so she could call out from work when she wanted because "the baby is sick". I always thought that was shocking- I guess because I tend to cultivate friendships among coworkers and don't want to lie to them.
I do think it's important for gays and lesbians to be out to everyone and feel that is what- more than any formal activism- has transformed broad public opinion in our favor. But it is tiring.