Unfortunately, that's simply not possible. No matter how hard society tries, people still die. Day turns into night. Love becomes loss. It's a fact of life.
So while everyone else is denying an entire half of life, the Goths embrace ALL of life, good and bad. Goths understand that the best and most lasting joy is tinged with a little sadness, and that all love is bittersweet. Goths understand that not everybody has to be happy 24/7, and that the way to succeed is not by pretending you are. Sunlit skies are beautiful, yes, but so are dark cloudy ones. What is white without black? What is a rose without thorns?
Thus, by embracing the shadows as well as the sun, Goths are, in many cases, actually more emotionally healthy than those in mainstream society.
Plus, we get to wear much cooler clothing and listen to far better music!
Boy #2: How do you know?
Boy #1: She's dressed in dark clothing and has those funky eyeliner swirly things. How weird. Let's go hit on her.
Boy #2: Just remember to mention that you totally dig Marilyn Manson.
Girl: Ugh, what a slut. Why can't she just dress like a real person? (stomps off in a jealous fit)