Winston Churchill was approached by Lady Astor at a dinner party and she said to him " Why sir, you're drunk." His reply was " I may be drunk madam but your ugly and I'll be sober in the morning."

So to paraphrase Churchill:

Yeah it's ugly but so are you and I'm on my way to trade this car in.

Or a great comeback from Cheers. You're a puzzlement to me. Usually someone like you with limited physical appeal make up for it with a actual personality.