Alone For The Holidays

I'm in British Columbia for the holidays.... flew in with my dad a few days ago. We're staying with his new girlfriend. She lives in a big house, with big windows, overlooking the big ocean and the big mountains. All the trees are big and the love is big and the feelings are big. I'm feeling very small.
I'm in British Columbia with my dad and his girlfriend and I'm feeling very alone.
We're here because I didn't want to stay at home, be in the home, be around the home this year. The idea of sitting in an undecorated living-room, the same living-room my step-mom died in made me a little sick to my stomach, so I told dad I wanted to go away.
I wanted a beach with hot sand and unbearable temperatures, he wanted his girl-friend. So, here we are. It was a free trip, so I'm not really complaining that we're not on the hot beach.
I am complaining however, over the fact that I'm feeling like a bit of a third wheel.
Drinks with neighbours, lunch at the pub, dinner with her family... it's all fine and dandy. I'm seeing beautiful sites and meeting some very interesting locals (I think EVERYONE smokes pot out here). But I'm still feeling lonely.
It's my first Christmas without Mary. My sixth without my brother. My eleventh without my biological mother. My friends are surrounded by their children, their partners, their husbands and wives, sisters and brothers, their aunts and uncles. I'm here with my dad. And her.
I like her. She's really, really great. She loves my dad, that I can see very clearly.
I guess I'm just feeling a little invincible. A little left out. A little affraid. A little alone.
I might of as well stayed at home, looking at all four walls of the living-room and felt this way there, in the comfort of my family home, as opposed to a strange place with strange people. I should have realized I would have felt this way no matter where I went.
***sigh***