Eddie goes to Angel's house because he now believes that Angel killed his cousin Jesus. Although Angel had been with Jesus when he died, Eddie had not suspected him at first. Over time, however, rumors and a realization of the depth of Angel's depravity have convinced Eddie that Angel had committed the ultimate betrayal and killed Jesus, whom he had called his carnal, or blood brother. Once Eddie believes that Angel is Jesus's killer, he works himself into a rage and goes to Angel's house to exact revenge. The two get into a prolonged and bloody fight, and though both sustain a number of painful wounds, neither is the victor. The fight ends when Eddie, realizing the futility of it all, enlists in the Navy so as to distance himself from an environment which is deadly for him.
I think it can also be argued that Eddie also went to Angel's house in order to take charge of his own destiny. As Eddie had been becoming more convinced about just how ruthless Angel really was, he became paranoid in a sense, living in fear of the plots he suspected Angel was hatching to get him. Just prior to going to Angel's house, Eddie had run into Belinda, the wife of a cholo who was in prison. Angel had appeared in an alley behind Belinda, and Eddie had imagined that Angel had arranged for Belinda to detain Eddie so that he could shoot him. Eddie had been trying to avoid Angel for awhile, and I think perhaps he was just getting tired of it. By confronting Angel once and for all, it is possible that Eddie hoped he could rid himself of the need to be watchful all the time. Sadly, escaping from the pitfalls that lie before him at every turn is not so easy, and Eddie enlists in the Navy because it is the only avenue that offers him even a chance to have a normal life.