help please

hello so a little back story.

I’m almost 18- literally like 3 months away.

Since like 7th or 8th grade.. well 12/13 I have been silently questioning my sexuality. I never said anything because I was young and I figured it truly was “just a phase”

I decided in 8th grade to “come out” as bi-sexual to my best friend since practically birth.. just to see her reaction. She lost it.. so to cover up I basically said just kidding and that it was a social experiment for school. That was that. Since then 9-11 grade I was positive in my mind that I was “straight” but in my heart I felt a pull toward both male and female.

12th grade starts- here we go. I get to know this girl who is bi-sexual and I start really liking her. I told her that I liked her- but she thought I was straight so it caught her off guard.. so I withdrew myself. That was october- now here we are in march and the topic has come back up.. but we’re much much closer now and pretty much 100% of the conversations are flirty. And she’s asked permission for if she feels the urge to kiss me if she could.. but here’s the thing

Since the beginning of this month I have finally started telling myself that I’m bi.. but I’m still too scared to tell anyone because of the instance from middle school. I’m also going to a christian college in the fall that has strict rules against lgbt. what do I do?

I mean she has come out to all her friends- but not her parents so I guess it’s kind of a 2 way atreet I’m just very closeted and I don’t have a clue what to do.