I don't think you're a wuss, ftr. I think you're human, like all the rest of us here. I spent a huge chunk of my marriage -- and even my early sitch -- paralyzed by fear too. For most of the very same reasons you state. I get it.
You've done a helluva lot more RIGHT than wrong, bro. And I respect ANY man who fights for his marriage, instead of doing the "cut and run" thing that society seems to promote these days.