Well not exactly disappearing, but it's going somewhere.

I have to put a gallon in every two-three weeks. I've been doing this for around 8 months or so since I bought the truck, but I can't find a drip or leak anywhere. Instinct says "head gasket" but I have zero symptoms of that. (I'm pessimistic with my vehicles....always worst case)

No coolant in the oil
No oil in the coolant
No bubbles the coolant
No smoking
Engine performance is normal as can be
Plenty of power (for a 4.2 V6)
No smell of coolant when I run the heat
No unusual moisture in the exhaust.

I can smell a slight aroma of coolant sometimes outside of the vehicle...

Given the fact of none of that taking place, could the gasket still be blown? Would there not be some sign?

It has gotten a little worse in the last month....that makes me hope that eventually ill see some coolant dripping...no more than it's losing right now though I would have to assume if it is an external leak, it's terrible small and maybe only leaks when under pressure....

Sorry for the ignorance, but I'm just not one of those mechanically inclined folks! I do appreciate this forum and the way people are always eager to help!

 

For being a confessed not mechanically inclined individual, you have an enormous amount of savvy. The slight amount of aroma noticeable is an area of concern. Check the lower radiator hose where it attaches to the water pump. Have experienced two types pump seal failures, static leakage or pressure leakage. Need to be sure hot and pressurized and cold and static the next AM. Staining on the lower hose should be evident.

Best way to confirm head gasket leakage is to use the Block check tester. If unfamiliar, air from the upper chamber of the radiator is drawn threw a certain liquid. The presence of CO2 will change its color, head gasket or crack in the engines water jacket is present.