I am bulimic and feel healthy, why is that?

I have been bulimic on and off, since age 13, now 21. i visited a treatment facility at the age of 18 and was able to abstain for a short while, but then soon reverted back to my old habits. I have read that this disorder causes serious medical complications and weakens your body. But i have been doing this for so many years. (purging daily 2-5 times) and i frankly dont feel weak at all. in fact i dont recall ever vomiting blood either. Am i just an exceptionally healthy person who can withstand enduring bulimia, or do you think it will eventually catch up to me? i do feel tired at times, but you cant directly blame that on the bulimia considering i am a college student and everyone here is exhausted.