Skibz888 is right, it's perfectly normal. No one is 100% heterosexual or gay, and those who consider themselves to be bisexual still tend to have a bias towards either men or women, it's never exactly 50-50. Although it can be painful, romantic love tends to be more profound and lasting than sexual attraction, which is often little more satisfying than masturbation (or even less so!) If you're lucky you might experience both at once, but again, either sex or romance will probably predominate. For all the pain I prefer romantic love and have nearly always experienced this for men; in fact it is a distinctive feature of gay relationships, whether sexual or platonic. Of course, you might be somewhat asexual ... it's more common than people think.