Are you me, OP? I feel like I have the same reason - on the rare occasion I do have a female character, I usually write her in a position of power, because I don't want anything bad to happen to her. This doesn't necessarily stem from misandry, however. It may just be a matter of taste - men who are hurt and downtrodden often react very differently from women who are hurt and downtrodden. (In part, due to cultural expectations - men are more likely to be expected to soldier through difficulties unemotionally, and this puts a bigger strain on them.) Or it might be very slightly kinky, if you're straight; personally, I find it both pleasant and unpleasant to see men hurt, but only unpleasant to see women hurt.
And there might be more reasons than just your love of torturing the main characters. Men and women do behave differently, and you may just enjoy writing the behavior of men more. I certainly do, for several reasons of my own.
I also wonder if it's because we're exposed to a broader range of male characters than female characters, so we are more at ease writing them. I know that I personally admire very few female characters, which is sad. I do worry about that, and am always looking for strong female characters in both what I read and what I write.
You want to talk, OP? Please, talk to me. PM me, AIM me, whatever.