Eavesdropping on WPA2 networks are not that trivial as in WEP or Open networks. Certain conditions need to be met (such as distance to the AP, frame rate and lack of beamforming) to be able to really decrypt the traffic. More information can be found herehere.
Also, you need to check if your POP and SMTP are sending information in clear text. Most of the email solutions nowadays support SSL, so your credentials most likely would be encrypted. You can check that on your email client configuration.