Lord if it's not to much to ask... Why me?

I let Lilly have some time to gather herself before I gave her a choice on what to do next. She cried for a while before she said anything. “What now? What happens next?”
“You have two choices. Come with me or stay here and fend for yourself. If you choice to stay I will understand and I’ll give you a few supplies and weapons. If you decide to come with me then you do what I say when I say it. Choice is yours.”
She seemed to be mulling it around in her head for a while before answering. “I’ll go with you.”
“Good choice Lilly. First thing I want you to do is take a long look at you dad lying there, I mean really take it in. This will serve you well when fighting zombies. Once you have it burned into your head we’re leaving. Grab what you want from your dad because once we leave I’m burning the house.”
I finished packing up a few items and found another pack for Lilly to carry, while she gathered items from her dad. I split the contents of my pack with Lilly’s so they wouldn’t be so heavy and started pouring gas around the house.
“Okay, we have about a half mile trek ahead of us to make it back to my house. I prefer to fight as few zombies as possible since we will be weighted down. Try your best to refrain from screaming like you did earlier, that will end up getting us both killed. Stay close and you’ll be fine.”
She never asked a question, did everything I asked of her, and never made a sound. On the way out the door I trailed a line of gasoline and lit it, saluted the fallen soldiers inside and we were off.
For the first time since the fall of man and the rise of the hell spawn, things went the way I wanted them to on the way back to the house. That is until we got about a block from the house. The house was surrounded by what seemed to be hundreds of the undead, and Tom was on the roof franticly firing the rifle. Lilly and I quietly positioned our selves across the street. I had Lilly climb a tree and handed her my rifle out of the gunnysack and got out some extra ammo for her. “Do you know how to use one of these?” She grabbed it out of my hand, pulled the bolt back, loaded a bullet in the chamber, released the safety, and nodded. “Good, aim for their heads and watch my back, I’m heading in.”
I grab my trusty hatchet, machete, pistol, and make sure my armor is on tight. I let out my battle cry to get the attention of the zombies and Tom. I hear the report of Lilly’s rifle and see one go down. She’s good and will make a valuable asset. Using the machete to decapitate and my hatchet to crack skulls, I make my way to the house. Tom is still franticly busting off shots and I can here Lilly doing the same, my focus is in front of me. Ever wonder what it would feel like to be an animal stuck in a piranha feeding frenzy? I felt like I was in it. Zombies lunging and snapping their teeth together all around, hands grabbing onto my armor trying to take me down, and blood was flying everywhere. Once I was close enough to the house I called to Tom to drop the ladder. He disappeared from the roof and a minute later the ladder came down over the wall. I yelled at Lilly and told her to get ready to make her way over and told Tom to cover her from the roof. Tom made his back to the roof and I made a mad dash back to Lilly. Lilly hopped out of the tree and I grabbed both bags and told he to run. There’s only about 40 or 50 zombies still shuffling around as we make our way to the ladder. Lilly makes it to the ladder about 10 strides ahead of me, she climbed up and extended her hand. I handed her the backpacks and she disappeared over the wall. As I made my way up the ladder I’m stopped by a zombie, it grabbed onto my leg and was trying to chew through my armor. I kicked it in the head with my free leg, but as I learned before they don’t give up that easily. I was about to drop down when Tom sniped it from the roof.
Once we were in the house things seemed odd, kind of out of place. Tom made his way down from the roof and met up with Lilly and me at the front door.
“Tom this is Lilly. Lilly met Tom. Now, what brought all the zombies here?”
“We have guests!”
“What! I told you to let no one in!”
“I know. I know. I really had no choice, they made their way over the wall and were going to break in.”
“Ok then where are they?”
“Well, I locked them in garage.”
“Okay. That still doesn’t tell why all the zombies.”
“They brought them with. I don’t know why so many kept showing up.”
About that time there is a loud moan from the garage, then an echo from outside.
“Did you check them? Where they bit?”
Tom didn’t answer just dropped his head, which was all the answer I needed.
“How many where there?”
“Four.”
“Lilly, you want to shoot some fish in a barrel?”
Lilly shook her head and put her hand out, she hasn’t said a word since I told her to keep quiet. I handed her the silenced Colt .45 and showed her to the garage. She threw the door open and shot three times then hesitated and backed away.
“What is it Lilly? What’s wrong? Speak!”
“I can’t do it.”
“What are you talking about? You just popped off three shots!”
I stick my head in the door and see the three motionless corpses on the ground and one now very fat child zombie. He couldn’t have been more than six or seven, missing a large portion of his neck and face.
“What’s the problem?”
“That thing used to be my baby boy!”