I can only write deppressing songs?

I have been playing guitar for over a year now and I've been writing songs during learning how to play. A lot of the stuff though I seem to come with is depressing or melancholic. It is also really trippy. I've written 1 happy song. I don't know why but my happy songs sound terrible and my depressing ones sound awesome. I was talking to a friend about this who is also a songwriter and just realeased his CD and all of his songs are kind of depressing. He says he gets into the song more when he writes sad songs. My other friend however said that I'm emo because my songs sound depressing. Even my dad said too. Something wrong here? Why cant I write happy songs?