I have been addicted to Afrin several times in my life and it is nasty stuff and hard to get away from. If you stay on it, you have to use more and more to get your nose to clear. It can cause heart rate changes and may actually keep you from getting a good night's sleep. Here are a couple of alternatives I have used successfully to break the habit:
Vicks inhaler, you know those things that look like chapstick and cost 1.89.
Vicks makes a steam inhaler. You put hot water in it and add a vicks tiny pad, put your face over it and inhale. (Your not suppose to put it in the microwave, but I did, it's like $8, I thought I could risk it)
Also, vicks has a new product called vicks shower tablets. You put them in your shower and the hot water makes a steamy vapor and opens your sinuses.
The steam inhaler is probably my favorite. Good luck!