What's wrong with being gay?

Gay
1 homosexual
2 happy and full of fun; light-hearted; cheerful
3 [attrib] careless; thoughtless

Recently I've read this post from Afterelton then I started to watch some gay-themed films. Last night my mum found out I was watching Beautiful Thing then she told me not to watch 'this kind of thing' in a weird tone. She despised it clearly. That's her, the most conservative person I know.
I don't see gay a problem. They are just different. The tagline of Brokeback Mountain tells the truth-love is a force of nature. I should say I feel the love between gay people is more tender, exquisite and smooth. It's a beautiful thing indeed. How come so many people think it's sick? Please stop doing this. Everyone deserves to love and to be love, equally.