there's always going to be a little resistance, especially if any energy is on the motor, ie it's on and you have regen set.
if you were losing a bearing, it'd be fairly noisy too, you should hear rattling, grinding, noises that just.. shouldn't be there. heft the bike up on the stand, turn it on and give it a little whirl, see if you can see / hear anything that may be off on it.
with that out of the way, the rear wheel should not give you problems in the front as you describe.
front wheel is always going to go roundy roundy because there's nothing on it, unless you are dragging a brake
back wheel is always going to be a bit stiff, it's got a chain / belt on it and is driving a motor, which if it's energized ANY, even if you are not riding, is going to have some sort of field on it, which may give you... lets call it magnetic braking/resistance. it won't go roundy roundy, it'll go, brrrR and come fairly quickly to a stop, because it's doing work, with no more active energy input to it, (you pushing it).
besides for cornering, any other oddities when riding, does it feel squishy, wants to wiggle around, which would indicate tire issues.
if you have a slow leak, you can get to the point where it suddenly feels like you are riding in mud.
with what jaime told you to do, tires should be checked every ride, as they often won't give you any indication they are low until it's very late in the game, and now they are critically low.
if it is a tire and you were at the point where it was affecting your ride that significantly, you need to check your tires very carefully, as that can damage them really quick. it won't be tread damage but cracking on the sidewalls and possible internal damage you didn't see. keep an eye on them for bubbling and things that would require an immediate replacement.
aaron