I assume those are iMessage texts - blue bubbles. That's because you have the same Apple ID, and you have set up iMessage to use your Apple ID. On each phone, go to Settings/Messages, scroll down to and tap on Send & Receive and choose either different email addresses or different phone numbers.
Alternatively, get separate Apple IDs. Otherwise all of your music and Apps will be duplicated also. See: http://support.apple.com/kb/HT1495