Why do I beat myself up

So most of my dear friends know what is going on. I'm going to spare the others the details. But basically DH and I are at a bit of a crossroads. Nothing to bad. Its mainly me. I just hate drama and it seems that once again drama has entered our lives. Its not his fault but at the same time it is. I tend to surround myself with good people. I have an awesome judge of character and can in just a few minutes of meeting someone tell you if they are a good person or not. About 99% of the time I'm right. If I don't find you to be a good person then I will choose not to hang out with you. DH on the other hand chooses to be nice and befriend everyone. It has bitten him in the ass way too many times but yet he still continues to give everyone a shot. There have been several times where someone has back stabbed him but yet he continues over and over to forgive them. I know that should be a good thing but at times when that character can be destructive to your family don't you think you should choose to not be friends with that person? Again its not his fault he didn't know his being kind was going to bite him in the ass but it did. And yeah its not his fault so why do I get mad at him and draw back from him? Shouldn't I be proud of that he befriends everyone and has such a big heart? Why is that the one thing I just cant stand about him and wish he would learn not to have? Why does everyone see that from him and use it against him? Most of all why do I let what they do bother me and I end up beating myself up about it?