I usually just reply with "I'm fine".. Which, to me, is being honest, because I'm just feeling neutral. Only problem with that is, alot of people then ask "JUST?.. fine?".. If I am "lying" and saying "fine" even if I'm not, it usually takes everything in me to keep from literally trying to explain everything.. So I usually (re)reply with "yeah, just fine", and then try to change the subject.
_________________
I think I've seriously under-explained my over-explaining.
Twitter @VaJayJayKrychek