I actually brought this up with my husband last night and he gave me the kneejerk response: nope, not okay ever, not if you're married, not under any circumstances. I think he must have heard the same talks as a lot of you

I do wish we could differentiate between "not okay for an unmarried 19-year-old male whose focus is supposed to be on missionary work" and "not okay for a married woman who probably isn't going to experience orgasm otherwise." But the leadership of the Church won't even say the word "sex"

so I don't think we can expect any kind of clarification.
I do think it's really unfair how the Lord designed our bodies differently. It's almost impossible for a healthy, functioning male
not to experience orgasm as the result of regular, garden-variety sex. And it's almost impossible for a woman
to. (This is a fact I've even seen acknowledged in LDS-centric sex books!) To me, that is another sign of how much the Lord prefers men over women, that he loves and respects males a lot more than he does females. Because the kind of sex that is generally regarded as kosher in the LDS faith is going to result in a male orgasm but not a female one.
I even explained this to my husband and he didn't have a good response, but he still will not back down on the "masturbation is always wrong, always" viewpoint. His argument is that masturbation is selfish and one-sided. Of course, regular ol' intercourse can also be selfish and one-sided but that has the Lord's stamp of approval (and it's almost always one-sided in the favor of the male).
I don't think it's wrong within a marriage and several posters have mentioned situations where it's even been encouraged by PH leaders. I would never judge or condemn a married couple who has decided it's within healthy and appropriate boundaries for their marriage. But as much as I may want to, I can't do it knowing that my husband is opposed to it.