I'm on my first cleanse. Is the SWF (Salt-Water-Flush) really necessary? I'm on day 2, and yesterday I barely got it down. Today, I only could drink 3/4 of it before I gave up. I tried warming it up, which made it taste better to me, but still didn't make it any easier to drink. Drinking the saltwater has to be the single most difficult thing for me so far. Even resisting the pizza that my roommate ordered wasn't as difficult. Any suggestions?