Why don't I want to come out?

[Person66]

Yes I was terrified of comming out, I may be bi, but I figured this would be even more confusing to people than if I were gay. However I live in New York, a liberal place. When I told the first person, it took forever for me to say it, the words just would not come out of my mouth and I was stuttering (I have never stuttered before) I also was saying it in a very roundabout way (mind you this was a friend who gay himself and about 10 years older) I finally got it out and I felt much better, though I have a feeling he thought this was amusing. Then one by one I told all of my friends, all the girls were perfectly OK with it, all but 2 of the guys also had no problems (those 2 just needed a little bit of time, then they couldn't care less).
As for my family, that was trickier. My mother is very liberal and accepting of these things, my aunt is accepting has gay friends, but believes a lot of stereotypical things about gays (like that we're extremely promiscuous). My younger brother is homophobic and bigoted in general. My father hates gays, but he has a reason, the only gay person he knows is his youngest brother, who is a total idiot, he always wanted his mothers love but she only truly loves her youngest son, however he lives alone and is very isolated.
So I decided to only tell my mother, I told her I was going to tell her something that might make her feel I was depraved, I then said I was bisexual and had slept with a man, she had a horrified look on her face after I said this and replied "yes, but tell me what you did that was depraved" lol. It was very anti-climactic.
I decided not to tell my aunt or brother, as I'm not close to them at all in any way.
So that's where I am.