Confuse, muddle, addle, fuddle, befuddle mean to throw one out mentally so that one cannot think clearly or act intelligently.
Confuse usually implies intense embarrassment or bewilderment.
Muddle often suggests stupefaction (as by drink) and usually implies blundering, aimless, but not necessarily unsuccessful attempts to deal with ideas, situations, or tasks beyond one’s powers of analysis or one’s capacity.
Addle suggests staleness or emptiness of mind and resulting mental impotence.
Fuddle and the more common befuddle imply confusion from or as if from tippling or indulgence in a drug that clouds the mind and makes one’s thinking and speech absurdly incoherent.