Israel and Germany aren't getting along

Israel cancelled a meeting with the German foreign minister, because he was going to talk with an Israeli rights group. The prime minister of Israel said he would not meet with people who meet with groups that look at IDF(Israel Defense Force) soldiers as war criminals. I think it's pretty dangerous for Israel to be picky with allies, and so they should be careful. I don't understand the whole relationship between Israel, and Germany but I think that it would be wise for Israel to be willing to compromise and not make a big deal out of things like this.