Why does'nt she like him?

my best friend hates my boyfriend...just because she thinks hes ugly and looks like justin bieber..well i tell her evn tho he does look lk jb i dont care about tht i only care about whats on the inside...and how she hates how he wears sunglasses inside...but i find it normal..she hates him for the stupidest things...but i lovv him..what do i do? I kno ur friends come first over boys but..what if i love him too much to lose?