Girlfriend sends pic to me and another guy?

My girlfriend will often send me nude photos over the phone as we live apart. I'm in the Army. I wake up the other morning and find that she sent me one. I didn't hear the phone beep that night so I checked the message status on my phone and see that the message was sent from her phone and sent to: Sent +my number, +another number. I did some research on the number and found that it belonged to a guy friend of hers that works in her same building. I asked her about it and she told me that she sent the message using a "recent recipient" option on her T-Mobile phone. That she didn't send it to him at all. It doesn't sound right. I want to believe her but its just not adding up right in my head. Can anyone help me with this one? Does anyone out there have a T-Mobile? Is there such a thing as recent recipient method of sending messages?
Girlfriend sends pic to me and another guy?
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