Black wedding dress

A girl goes to who wedding,
but not wearing a white dress,
instead it's black as night,
because she's morning and under stress,

she knows he grooms a cheater,
with her own sister,
but oh boy,
is he a good bluffer,

everynight he told her he loved her,
when he proposed he made her day,
he made her so speechless,
there was nothing she could say,

then she heard a noise,
she peeked through and there they were,
it was her own sister,
instead of her,

so it's her wedding day,
she's mourning and under stress,
her groom is a cheater,
so she is wearing a black dress.....