Galermo, of Bellflower, pleaded guilty to three counts of acquiring access cards to defraud, two felony counts of second degree commercial burglary and one felony count of receiving stolen property.
Investigators say she removed colored greeting card envelopes while sorting mail between March 2008 and July 2008.
The Postal Service began investigating after receiving complaints from Orange County residents that cards and mail containing gifts had not arrived.
Investigators said Galermo used stolen gift cards to buy items at two Target stores.
Investigators found stolen mail and envelopes addressed to other people in Galermo's trash outside her home.
Galermo no longer works for the Postal Service.