Yes, it is a fixation of the church and has been for a very long time.
Here's one of my favorite masturbation quotes from the church, given in a general priesthood meeting:
I am going to use a visual aid tonight. But we don’t have one, so, in your mind’s eye, wherever you are across the far corners of the earth, would you picture a huge scroll sliding down from the ceiling? On it are listed the names of those who purchased pornographic literature. The list is large enough so that all may see. Is your name on the list?
Did you buy some pornographic literature?
Now suppose those names are removed, and the names of all those who attended or viewed x-rated movies are presented so that all who are in the congregation may see. Again, is your name on the list?
Now, my young friends, and I am sorry to say, many adults, how about all those of you who have a masturbation problem? If the names of those who had the problem were projected across this big, huge scroll, would your name be there, or would you be able to sit back confident and pure in heart? (Vaughn Featherstone, "A Self-Inflicted Purging," Ensign, May 1975)
http://LDS.org/ensign/1975/05/a-self-inflicted-purgingIf we're fixated on it, it's because the church taught us to fixate on it. It's frankly disgusting how some people dismiss this issue as some perverted fixation of apostates. It's not our fault that the church made this such a big deal in our lives. I stopped masturbating for 2 years before my mission and then through until marriage, and I still felt guilty. I was taught to feel guilty, but some urbane, sophisticated person who apparently missed the church's teachings has the gall to condemn others for having any feelings about this issue at all.