Long road
I am trying to do things to work on myself to be better for my wife and kid, but sometimes things that would otherwise be a small thing to my wife seem to make her extra mad at me. So I get down on myself more because I know I caused the shortness in her temper now. Just gets hard!
I admire your willingness to be open to change and to work on yourself, I'm sorry you're stuck in a frustrating situation, but I'm sending good thoughts your way for the road to shorten a little as soon as possible 
Glad you're here for support! It's hard when you're doing so much work and it's going unnoticed or even bringing on a negative response, so I understand why you'd be struggling.
I do this to my husband every day. I’m chronically discontented and it really affects him. I’m a perfectionist and like things just so. It’s so hard on him. I’m sorry you have to deal with this. It’s really not fair on you. It’s probably more your wife than it is you, or maybe you don’t yet understand the things that are important to her or think she’s being ridiculous. Try to see things from her perspective more. But remember that no one causes other people’s feelings—they decide how they feel.