In Need of a Force Field

A friend has been promising to build me a force field for quite some time now. There are moments in my life when I really could use it. Not because of any kind of physical abuse I take, but because of those people who can utter just a few words and cause tears to start falling from my eyes. And they don't even realize they do it. And I think that may be the most frustrating part. I end a conversation in tears, and this person goes on his merry way, with no clue how hurt his actions and indifference make me feel. I have tried in the past to do one of two things. The first thing I have tried is to not let it bother me. Why should someone else have control over my emotions? Why should someone else be able to spoil my day so easily and make me feel so bad? No one should have that power, but as hard as I try to not let it bother me, it does. The other thing I have tried in the past, and it is about time for it to happen again, is talking about it. The problem with this strategy is that the other person isn't frustrated so has no motivation to change the situation. And he doesn't deal with problems like this well - his solution is usually for me to get over it. Which brings me back to my first strategy, which doesn't work. I wish I had my force field, and I could put it on every time I talked to him. I wish I could have a relationship where he didn't affect me and the way I feel. But I don't know how, and my friend hasn't built me my force field yet. I sometimes wish I could cut this person out of my life, so he couldn't hurt me anymore, but I can't. Because he's my father. I don't know what to do.