Its been a very tough week

If you know me at all, you know very well that I do not do very good at funerals. And until recently I believe I have been blessed to not have to go to any. I went to my first funeral in a long time this past Saturday in Comanche, for one of my dad's best friend's son. Although I did not know thier son Steven very well, I went for support of my dad's friend Denny. It was hard, just like every other funeral for me. I'm a very emotional person and seem to be able to cry at the drop of a hat. Especially when someone else around me is upset and crying. Just seeing someone else cry that I know makes me cry.
On Sunday I got some horrible news from a very close friend of mine that her mom had passed away. She was only 41 and I had just seen her a week prior to her death and she didn't look sick, and I guess thats whats most shocking, that death can just come out of nowhere. This one hit me really hard. She was an amazing womand that I could talk to about ANYTHING. She was like a mom for me. I mean I was always over at their house and for the longest time I never knew her first name. I always knew her as Mom and not Laura. I have cried off and on since I heard the news. Her funeral is Thursday.
Now I've heard stories, or I guess you would call them superstitions that death comes in threes. I'd been dreading the news of another death. I felt like my heart just couldn't take it. And then it happened...
This morning the alarm when off at 5. I got up just like any other day and was starting to get ready. I brushed my teeth and was about to get dressed when I decided to crawl back into bed. I was laying in bed when I saw my cell phone light up the dark bedroom. It was my house calling. Weird...I thought. Why would dad be calling. (He's the only one that comes in at work at 6 like I do, so I knew it was him) I called the house back about 5 minutes later, no answer. So I put my shoes on and called Dad's cell phone. He answered, figured he was going to ask me about the rain/storm we had last night. But no, he gives me the horrible news that his dad, my Grandpa Turner, has passed away. He'd had an aneurysm by his heart and I guess was in a lot of pain last night and he and my grandma went to the hospital. They were prepping him for surgery when he passed away at 3 this morning. I'm absolutley devistated. And the worst part? My grandma doesn't know yet. They sent her home before he went into surgery so that she could get some sleep and I guess after she left is when he passed away. When dad gave me the news, of course I cried and for I think the first time ever I heard my dad cry. And I think thats what gets me the most. He's always been the strong one, and I can't imagine the pain he's in right now.
So why is it that death comes in threes? Does anyone know the answer to that?