I'm in a regular game..why can't I win? Here are the details...

I play in a regular game. We start with $13,000 in chips with $100-$200 blinds. The blinds increase every 20 min until we get to $5000-$10,000. Then they start increasing every 15 minutes. For the first 3 rounds, we allow rebuys if your $2500 or under for $6500 more chips. After that, no rebuys. We also allow an add-on after the end of the 3rd round for $6500 more chips. Our usual game is anywhere between 12 and 16 players. I usually play pretty tight in early rounds and tend to loosen up when we get to about 6 players left.

Lately, I can't seem to win. I find that I'm always the short stack and that I'm playing to last. Most of the players are pretty loose so I always try to sit back and wait. My style is pretty similar to a Dan Harrington where I don't call too many raises in early position unless I'm holding a premium hand. I generally don't call Ace rags unless it's later in the game. How would you play something like this? Should I just chalk it up to a run of bad cards?