Like Father, Like Daughter

I'm a little scared right now. I've always known that I had my dad's stubborn streak and high-mindedness about certain things. I also know that much like my dad I'm prone to self-deprecation, which works in my favour to a certain extent because at least that part of my personality keeps my ego in check. However more and more I'm realizing that my dad and I have something else in common, something that I don't particularly like: passive-aggressiveness. My dad being mad at me has always been worse than my mum being mad at me because my dad doesn't yell. There's no outward show anger at all. He stews until he hits his boiling point, which doesn't happen often. He mostly just stews and acts in a passive-aggressive manner towards the person/people he's mad at. With yelling at least you know what you're getting.
For the past few weeks I've been extremely frustrated with Hunter for a myriad of pointless reasons. I haven't said anything, but lately I've made snide and sarcastic remarks when he and I actually get a chance to talk. Today when he said he was going to hang out some knitting shop down town I told him I hoped he had fun with his yarn. Even though the statement was typed I was thinking it in my head with a bitter and sarcastic tone. What scares me about this is that it's so easy to just continue down this road, never confront the issue, just make pithy and cutting remarks instead. I'll continue to feel bitter, Hunter will remain completely unaware of the problem and nothing will get better, it will just get worse. This relationship is so important to me, but inertia is working against me and I'm too much like my dad. I'll let the problem stew until I hit my boiling point at which point everything will go to hell and a hand basket. That scares me, but I seem incapable of doing anything to change it. People say the first step is admitting you have a problem, but then what? How do you fight inertia?
God, I've gone so emo. At least I still listen to relatively happy music.