Masturbation≠Lust. Just because some acts of masturbation involve lust does not mean that they “go hand in hand.”
I think we have to consider two things- what our bodies tell us and what God tells us in scripture. I personally can say that when I hit that age, my body started giving me what I would call whispers. I would ignore them, because I accepted the Church teaching despite disagreeing with it. However, over time the whispers became urges, and the urges became demands. From time to time my body would get tired of waiting for me to satisfy it and do so on it’s own through nocturnal emission. This continued on for quite awhile in what was probably the worst self imposed period of suffering I’ve forced myself to endure. The biggest problem, for me, was the effect this had on my ability to think. Ever heard of Maslow’s Hierarchy of Needs? It basically breaks down all aspects of human desire in places them into groups, often represented as a pyramid. Physiological needs, such as the libido, are at the very base of the pyramid- higher reasoning functions are at the top. As such, my ability to think, understand, and comprehend were so far bellow what I had become used to that I asked myself whether or not it was worth forcing myself into that existence for a teaching I disagreed with- and the answer was no. There was no lust involved in that decision, just the fulfillment of a natural urge.
Now- onto God’s take. We can assume that the human libido was no less strong during biblical times- apparently, getting to “know” each other was quite a common event. As such, the urge to relieve one’s self would have been just as strong. Now just because there is an urge does not mean “Do it!”. I acknowledge that: vengeance, greed, and gluttony are all natural urges as well- however, for the urges we were not supposed to fulfill God said “hey, don’t do this!” in scripture, albeit in different terms. Leviticus condemns every sexual offense from homosexuality to bestiality, with no mention of masturbation. So we have an urge that God seems to have specifically excluded from condemnation. To me, that sounds like tacit approval- making masturbation an amoral act.