Katt: You guys need 2 computers!
The only way I know to keep track of time is to watch the Sun. It's generally best to start the Monk quest close to sunrise or sunset, as that's pretty much the only true measure of when a day passes. If you start in the middle of the day or the middle of the night, wait until the next daybreak or sunset after the two day interval before you check back in just to be on the safe side.
Game time to real time is variable, depending on what you're doing. I've noticed that if you're talking to NPC's, time shoots by, as it does if you're battling monsters. Just walking around makes time pass by normally, and standing still will make time pass very slowly. Best bet is to go visit wilderness NPC's (Erzebette, Kerielle, Bilbump, Jathil, etc.) and talk repeatedly about everything. Time seems to pass very quickly that way.
-Sazerac