The queue for PvP is different from other instances. Some people consider it as a bug while others say it's working as intended. In any case you will usually get stuck in dead queues; how it occurs it's beyond me.

The "trick" we use in my PvP LS is simple. Re-queue every 10min of waiting since it seems you can get into PvP depending on your assigned instance NOT queued time. Check on the in-progress too and if someone tells you they got into a match then re-queue again hoping to get into the instance assuming someone drops it which occurs quite often.