Active 433Mhz RF tag battery life question
It's hard to say what exactly is going wrong in your setup, but I've design 434 MHz active RFID tags that sent a packet every 10 seconds and ran for a whole year on a CR2032 battery.

30 bytes is way more than necessary for basic identification.  Our tags sent around 80 to 90 bits per packet, which was somewhat data dependent.  That was enough for a 32 bit unique ID, a few bits of status information, a 20 bit CRC checksum, and the usual preamble and stuff.

Using a complete RF communication module is also inappropriate if total power is a priority.  We used a bare transmitter chip and toggled it on/off directly by the firmware.  This isn't that hard.  In one case this was all done by a PIC 10F202, and it only used about 3/4 of the code space.