I had something similar happen to me man. My girlfriend of a year and a half dumped me for a 21 year old. Just outta nowhere man. Calls me..."I have feelings for someone else..."
She still calls and texts me from time to time telling me how much she misses me and shit...and I'm all..FUCK THAT SHIT. She is 15...and I say "Welll..things aren't going well with you and him BECAUSE...he's a god damn adult...and your A CHILD"
They say guys are the assholes and heartless jerks...yeah...girls know how to fuck up a dudes heart better than a blender...
-.-