How Can i tell if my best friend is bi? ( sorry d typing had 2 make it fit some how.)?

My best friend and i r really close we tell each other everyting, we've been thru thick and thin. However my oda friends told me dat 2 bcarful, wen i asked y dey said dat she is bi. Dey r nt sure bt dey told me dat d way she looks at me sells it out. I neva really noticed anyting suspicious, d only ting i noticed was dat she gts jealous wen i tlked 2 oda ppl &she wud watch dem really hard / she'd do somethin 2 win my attention bac/ she'd hug me wen dey left but i didnt tak it on i thought it was a norm besfrd phase.bt i stil took wat my frds said in2 consideration. 1 day i noticed wat my friends wer saying but she neva noticed, i remembered wen seh came 2 spend sum days by me,d way she looked @ me really promiscuous/ sly wen i cam out of d shower i wanted 2 change my clothes. I neva change my clothes infront of her though. Is my besfrd bi? I wont eva abandon her if she is cuz we've been thru alot 2geda. Even if she is bi i'll accept it. I'm jus afraid to ask her if she is.