Why am I stuck in-between?

I have a recurring dream of myself chasing a girl. At first it turns out to be light at positive, she is skipping and I'm chasing after her, almost like frolicking. But then it turns out as a more vivid chase as something more important. Then It is like I desperately need her. Then my girlfriend appears in my dream and then I'm chasing after the both of them. It turns out to be that I am chasing them for sexual reasons. All of a sudden a gay is chasing me, I turn around and I sadistically kill him, cutting him up. Sometimes killing him will be short or long, but then after I get lost and 1 girl appears and it either switches between my girlfriend or the other girl. What in God's name does this dream mean?