stupid talks with my parents

so we had lunch and we talked for a while and i really don't know how we got to that theme but i think it's not that important...
my mother always says if i'll have a boyfriend she would kill me if he's black. she's not a rasist, she just wants to get me angry. please don't think me or my family are against blacks. that's bullshit!
however.
she just wants to argue a bit and i'm sure everyone knows these situations. i'm not that good in fighting back but i tryed and so i said one day i'll shock them and have a girlfriend. my father was like "you can do everything but not be a fucking lesbian!"
i'm not sure if he was hornest but both told me that they wouldn't be fine with that...
the problem is....
i AM a lesbian. or maybe i'm bi...i'm not quiet sure. the only think i know is that i like girls and i always thought it wouldn't be a problem for them but maybe i was wrong....