Alex takes Kate and Peace home from the hospital. Michael goes in the house as Kate takes a shower. Alex comes by, and Michael threatens to kill him if Madison tips him off. She holds it together, but Alex figures out that something is wrong, and bursts through the door and has a fist fight with Michael. Michael strangles Alex, but Madison convinces Michael not to kill him, by faking Michael out about reconciling with him, and stabs him in his side with a knife. She calls for help, and manages to get the handgun Michael had, and kills him in self defense.

Who died in til death do us part? Let's have some stream of consciousness first.
The relevant sentence in the passage is: She calls for help, and manages to get the handgun Michael had, and kills him in self defense. So, the answer is Michael.